Hacker News new | past | comments | ask | show | jobs | submit login
Show HN: I built an app to use a QR code as my doorbell (dingdongdoorbell.com)
140 points by dirkc 36 days ago | hide | past | favorite | 231 comments
I didn’t have a doorbell before (multiple reasons) and my house feels unwelcoming without one. So I built a doorbell app that uses a QR code - visitors scan the QR code to ring the doorbell and I get notified on my phone.

Here is an example of the QR code I have on my door. You can scan it and say hello: https://www.thebacklog.net/img/2024/10/show-hn.png

This was also a great excuse to build my first app for Android and iPhone.

I’d love to get some feedback before I spend more time polishing the app. Please try it out and feel free to ask me any questions! No logins or accounts needed.




Hey! Welcome, valued visitor! You’ll notice I don’t appear to have a doorbell. Don’t worry, this is for your convenience and mine.

If I’m out and about you’ll be able to contact me, and I can tell you that I’m unable to answer the door right now but I value your visit.

All in real time!

Let’s get started: simply solve the puzzle below. The solution will let you work out the code to unlock the box next to my door.

When you unlock the box scan the QR code inside, which will allow you to connect to my WiFi guest network.

Once you’re connected scan the second QR code to open the virtual doorbell selector. You can then select the appropriate message for your visit.

Unable to connect?

Simply knock on the door and wait. If I’m home I’ll surely answer soon enough. If I’m not home or don’t want to be disturbed you should use your own judgement: if it’s urgent trying shouting through the letterbox, or maybe wait a while and then return later!


Your privacy is important to us! All interactions with this QR code doorbell are recorded for the purpose of training and quality improvement. If you do not want your data to be stored, please opt out by scanning the second QR code below the QR code doorbell. This doorbell uses cookies to enhance your bell ringing experience. Using the QR code doorbell implies your consent to the use of cookies and similar technology. To reject the use of cookies and similar technologies, please scan the third QR code below the QR code doorbell.


In the right circumstances that sounds like fun - a mini escape room before you can visit your friend :)


I’m wearing mittens >:-#


This does seem like it might be prone to pranksters copying a particular doorbell code and putting it outside someone else's house (or several houses), distributing fake flyers that include it ("Scan here for a chance to win a cruise!"), and so forth.


My immediate thought was: get an esp32 with an eink display and regenerate the code every ten minutes, but of course we've left the extremely easy realm quickly.

But I agree I wouldn't want a static QR code linked to anything that could bother me.


Then, why not hook up a button to said ESP32 and improve the UX by multiple magnitudes?

Oh.


I know I know. The QR link can resolve to a captcha/puzzle that needs to be solved before it actually rings!


Also we'll serve ads on it.


Choose the quarter pounder in all of the photos…


Choose the quarter pounder with e.coli in all of the photos would be beneficial to the vendor as well


It will use a LLM to interview you and decide if you are allowed to ring the doorbell


But LLMs cost money so it'll need a monthly subscription with tiers (for visitors too!)


Please insert 25 cents to continue this call


Wait, hold on.

Let's make the doorbell an NFC payment touchpoint. Tap and pay 25 cents to ring the doorbell.

The more you tap (and pay), the more the doorbell will make an effort to reach the person on the other side.

Wanna pay $20 to the doorbell? Sure, I guess it can ring my phone to let me know someone shows up...


How to massively over engineer a simple doorbell!

I don’t mean this in a mean way and realise that your comment was mention the spirit of the conversation :)



You could also just use a cheap pet-compatible motion sensor and sound the chime when there’s motion on the porch.


That sounds like a lot more setup than simply slapping a QR code somewhere doesn't it?


I build apps for a living, that solve real-world problems.

Static QR codes make no sense by themselves because they can be replayed. Same goes for "pay with your face" biometrics. The person is supposed to confirm something on THEIR OWN phone, to authenticate themselves and their location. Then the QR code to scan can indeed be static. Since the person's phone has to have the Internet anyway to make requests, simply change the interface on the PHONE.

QR codes printed on a flyer or wherever are meant to "start the conversation". The authentication can happen right after. But keep in mind that, by themselves, they are not enough. For example, if you're trying to do a ticketing system or attendance where people scan a QR code, they can just forward it to their friend. Better to have them PRESENT a QR code to be scanned.

Having said that, WiFi access points and captive portals are better. Because once you authenticate, the next time is seamless. They can be used to take attendance in classrooms, and much more, seamlessly. (Except if it a person's phone is off. So then they have to come up and manually register, or you have to find that out by having a challenge during class that actually requires phones.)

ATTENDANCE ONLINE:

While I'm at it, I will mention one more thing. Authentication and "presence" can also include face recognition and eye tracking. There are lots of models for Tensorflow's JS port, such as "blazeface", that can do it in real-time. You can present a computer interface on your own wall and the person is authenticated with their face. But remember, once again, that this should only be used for your own software within your own organization, which you presumably trust. Because it can be replayed and spoofed by whoever has access to the back-end.

Anyway, for remote learning, this becomes really useful because (e.g. during the pandemic) the teacher can have an on/off signal which M of N students are paying attention, and which are drifting off or walked away from the computer -- all WITHOUT seeing their video feeds. So it enhances privacy.

We've built a simple tool where students can open a background tab for instance, which watches where their attention is, while they use whatever sites. The tool is deployed by the teachers.

If you want to prevent tech-savvy students from spoofing this attendance, you have to ship some of the code, signed with your own HMAC or private key, every time, and do it in a third-party iframe so their JS code can't simply override it. They would have to rewrite the code in the time that the secret key for the HMAC changes (every 10 minutes). For that, they'd need to install their own user-agent, and very few students are going to go that far. But yes, if people do have their own user-agent, then they can pretty much do any kind of replay attack for attendance. Something to keep in mind.

The only way I have found, to do attendance reliably online, in the presence of adversaries capable of wielding their own user-agents and rewriting code on the fly, is to have them join a videoconference and show a signed QR code on their phone while also completing challenges with their face. The private key might have to come from an agency that saw them arrive in person. The only way to defeat this is to corrupt the agency, making it give out a lot of private keys, and then deploy deepfake video avatars at scale (the kind DARPA wants to do) to complete all challenges. At that point, they AI is probably good enough that you prefer the bots to humans anyway LOL.

SYBIL ATTACKS

I will also say a word about sybil attacks. The best ways I have found to prevent them are imposing a cost (but those who can recoup the cost will still do it) or grandfathered accounts. The problem with grandfathered accounts is that people can deploy software to automate existing accounts, and do it occassionally enough to avoid detection. The only way to prevent cheating in tests, for example, is to flip the classroom and have the students take the test in class. They can do it on their phones, as long as their phones notify the teacher when they put the app in the background. (However, there are still problems with phones that allow multiple apps side by side and don't tell the apps.)

In case you are wondering, we are building some of this stuff on https://teaching.app


>all WITHOUT seeing their video feeds. So it enhances privacy.

I'm sure your app doesn't actually stream the video back to the server, but how do I as the user, know that? All I can see is you requesting camera permissions and you saying "trust us bro" that you're not streaming the feed back to your server.


You can say that about literally any app or piece of software, as a regular user you just "trust" WhatsApp to do end-to-end encryption, or websites to not read your email and try your password on other websites https://xkcd.com/792/

Mostly, in our use case, it's because students are already willing to open their camera to teachers, when they demand it, and this is actually considered a more effective and private "upgrade" for everyone.


I'm not sure what all of this has to do with the OP?

The way I understood the submission is that if you don't have a doorbell - or especially a smart one - scanning the qr code replaces pressing the button.

Others have mentioned that it would be easy enough to copy it and circulate elsewhere but while that's a big issue in my books I don't see the link to captive portals, student attendance etc.


I started by addressing the OP and the issue of replaying the QR code directly.

And then I branched out into related issues of proving presence somewhere — online or offline.


Easily pranked yes, but not that different from other cases which turn out to be non-problems in daily life.

People could also print flyers with your phone number on them. Add your email address to spam lists. Etc etc.


Generate a new code when it happens? It's not like you have to keep the same QR code for some comptibility reason.


I think this could be solved by asking the last name of the person/family you want to ring the bell for, once the QR code URL is loaded. This doesn't solve the issue of: what if multiple appartements want to use this solution as a doorbell? Then you'd have to add the name on the QR code and it's back to square one.


I'll be honest, if I have to scan a QR code and fill in a form to let someone know I'm at their door, I'm turning around and going home.


Not even trying to knock on the door?


there is probably very little cost in changing the QR code, almost like changing a password in an odd case that anything like this happens.


Wouldn't you also need to reprint the barcode? Get it's probably unlikely to happen, but there seems to be a lot more friction than changing a password.


You could rotate them at random so you're only printing a dozen or so.

But again, still more hassle than helpful and if you forget to switch it the problem remains.


Swapping codes on two adjacent houses would be pretty amusing.


Pranking is a legitimate concern. What do you reckon the worst case scenario to be and what do you reckon are reasonable pranks?


Worst case? I guess that would be so many bogus notifications that your doorbell is rendered effectively useless. But in that case, I suppose you're moving out of the realm of pranks into what is essentially a DoS attack.


Choose better UX design.

1. Get a QR code to put at your door

2. Visitors scan the QR code using their smartphone camera

3. Get a notification on your phone wherever you are!

OR

1. Install doorbell at your door.

2. Visitors press the doorbell using any of their extremities.

3. Get a notification on your phone wherever you are!


The other good thing about Option#2 is that visitors do not have to give you their mobile phone number (which they are doing by sending the text).

Just because they are at your door for some reason does not mean they want to give up what has become their mobile ID. People are starting to get protective of it with good reason, since there are so many attacks using the Mobile #/ID...

Also, as pointed out elsewhere, the static easily duplicated QR code has issues for you, but it would also be easy for someone to slap a malicious QR code over your static one, disabling yours and enabling their scam...

Maybe I'm just the wrong generation, or live in a place that still has winter, but a QR code where I need to get out my phone, take off my glove in winter, activate the camera to scan, etc., seems a lot less welcoming.

One thing that is good about your QR code option is that you do receive notice anywhere and you do have their mobile number, so you can reply immediately with a text or call, such as "sorry, I'm running late, not quite home yet, I'll be there in 10min". Ofc, you could also post your mobile number below the wireless doorbell.

Perhaps Option #3 would be a doorbell that can display a scrolling message, so

— wireless doorbell

— sends text to you

— you can reply to doorbell (e.g., "coming downstairs now", or "traffic, be there in 5min", "pls call me at 987-654-3210", etc.)

This way, no one needs to reveal their mobile number, but everyone has the advantage of mobile communications, albeit with a small bandwidth.

?


How did you come to the conclusion that the mobile number is in play anywhere?!

From what I read it says to scan the code and get a notification anytime it's scanned. Just looked at the android app listing and there seems to be something about taking a selfie which seems rather useless but hey maybe some people like it.

Also love how people keep suggesting wireless doorbells when the whole point of this is not to install any hardware that could be to expensive, harder to setup/maintain than a QR code, or maybe stolen/damaged or not allowed to be installed


Seems it is the visitor's phone scanning the QR code, which means whatever mechanism sends the text has all the identifiers of the phone which scanned the QR code, right? If it protects the visitors' numbers from disclosure, that's great, but there is no assurance (and none that could be given and absolutely trusted) that they are not disclosed.

OK, maybe the point is to not install any hardware (beyond a sticker), but it seems people are pointing out that a QR code introduces more problems than it solves (trust, spoofing, copying, misdirecting, inconvenience, etc.). If he wants to install no hardware and get a text on his phone, perhaps the easiest thing is to post a sticker with "pls text me at [mobile number]" at the location of the doorbell or QR code?


It would be possible to encode the phone number in the QR code and just send a text, but then you could just print out the phone number and write "text me" next to it.

Given that they have an app I'm sure the QR code leads to a link that will trigger the notification via app on the phone, no text message anywhere.

Again to your last point, no text message, dude just wants to get a notification on his phone without installing some dumbass $300 doorbell


Choose better UX design from visitor's perspective

Knock on the door while ignoring anonymous QR code that could have been left by anyone


This is my nr 1 question, will visitors scan the QR or will they still prefer to knock/phone?


I hate it when people call/text me to say "I'm here". You know what else you could do to let me know that you're here? Knock or ring the bell. It's definitely a generational thing though. Having lived in a time with and without devices, I'm really thankful that I didn't grow up never not having a device. This is a good example of unable to think of how to operate without a device


One reason I and a number of people do that: to cover the possibility you might be at the wrong door/house or ringing the wrong doorbell.

I had both of those problems at my previous residence. It was an apartment complex with some N½ addresses. Visitors would often miss that bit and be at the wrong door. On top of that, the doorbells were counterintuitive: they were arranged vertically, but the bottom doorbell would ring the top apartment and vice versa, so I forever had visitors and deliveries ringing the wrong bell (and actually mostly for the other units ringing mine.)


Also if someones just dropping by (unscheduled delivery, sales) and I'm asleep, or watching a movie, or whatever I don't want to be disturbed, and if I have a question for my neighbors similarly I don't want to bother them if they're busy. Phones have snooze mode, most doorbells I've encountered don't.


I usually text/call when I visit people not so often like once a year or once in couple years because usually I don’t remember exactly which number it was.

If I go somewhere couple times a year I usually feel quite comfortable using doorbell.


I do this all the time even when I know I'm at the right place as my friends have young kids and I usually turn up around when they might be in bed, so I tend to just message my mate I'm there to see that I'm ready and outside. Both of us are in our late 40s.


Wow that’s a surprisingly aggressive comment. I’ll share why I used to text and call “I’m here”. I’ve had many experiences where the residents had dogs that would absolutely lose their minds and bark non-stop or go crazy when you ring the doorbell. It’s just a better experience when their owner opens the door and there’s a guest. Other times, my friends lived in a multi-unit apartment and I didn’t want to bother 5 other people who I didn’t know. Other times they lived with their family and, again, just didn’t want to talk to them that time. -shrug- but I guess these are examples of not being able to think without a device.

For you, if you’re expecting guests, just tell them to ring your doorbell. Get rid of the ambiguity and give them comfort in knowing the “right” thing to do. You clearly gave it some thought and have strong opinions about it. I’m sure other people are just trying to be considerate in a generation where they mostly grew up living with lots of other people.


> For you, if you’re expecting guests, just tell them to ring your doorbell. Get rid of the ambiguity and give them comfort in knowing the “right” thing to do

I'm not the person you're replying to, but the way I see things, if I put a button on the front of my house labelled "visitors, please press me" and then I got mad at my visitors for pressing it, that would be super weird behaviour on my part. The button is the permission.

People who don't want visitors to press the bell either remove it, or tape a bit of cardboard over it or something.


Sure, I think if a doorbell exists, it's fine to press it. For me, I just don't want to get overwhelmed by their barking dogs or greeting 4 other people. Sometimes, I'm just not in the mood and just want to see my friend one-on-one. I'm not doing it for other people. I'm doing it for myself because I find the experience of calling someone when I arrive to be a lot more pleasant in some cases. Those cases happen to occur more often when my friends are young. i.e. living with lots of other people or with their parents and family dogs.


Well, usually.

Our doorbell, which was non-functional from when we moved in until we moved out eight years later, and which we were always planning to fix 'next week', is a good counterexample.

Not that we'd get mad at people for ringing the doorbell, but we were very glad that people usually figured out they had to knock.


I hate when people ring the doorbell. I'd rather they just walk in so I don't have to get up.


Some places don't have functional doorbells, and some doors are too far from living space for a knock to be heard.

Some renting situations make solving those problems difficult, annoying, or impossible.

But yeah, generally a doorbell is a pretty reliable tool.


> Some places

That's probably true, but I don't live in some places. I have a door with a knocker and a doorbell. Calling/texting me is so damn annoying and pointless. You knock/ring, I get up and answer the door. You text/ring, I might ignore it or at least it could take time to go to where it might be sitting other than in my hand.

If you live in one of these "some places", I doubt the landlord is going to be very happy about people plastering various QR codes on their property, especially if "some place" is a multi-tennant property which typically already have a system in place


> but I don't live in some places

Great. I don't think OP made this thing explicitly for you.

And I'm not attempting to persuade you into choosing this doorbell option.

For others, who are not you, and who have different living situations than yours, this could be an interesting option.


The ‘system in place’ in question: two non-functional doorbells, a third wired up to your housemate’s room, and a fourth which only works on Tuesdays (nobody in the house knows why). :)


I disconnect that shit because of unwanted use.

Mailman, flyers, delivery not for me, neighborhood kids pushing wrong buttons or just fooling around.

If I have delivery scheduled or there is scheduled maintenance for building I will connect it for that day. Even delivery guys sms/call me when they are in area to check if they should drop by with parcel anyway.

People like friends/family don’t drop by without calling sending a message. There is no unscheduled visits since I was teenager.


I get annoyed by people knocking instead of ringing the doorbell. I am less likely to hear a knock.


I would not scan the QR code because that’s way less trouble. If the owner insisted on it I’d do it, but I’d roll my eyes and wondering why the owner thought this was an improvement.


I probably agree with your premise (it's not clear), but:

Scenario 1 (QR code) puts 100% of the infrastructure on the client (visitor) side, and scenario 2 (Nest, Ring, etc) puts 100% of the infrastructure on the server (resident) side. [Edit: strained metaphor perhaps, and yes both scenarios require connectivity infrastructure]

So these are completely different methods of achieving the same goal, and there are easily imaginable cases where one scenario would be preferable over the other.

Usually, server-side makes the most sense. Certainly in the case of a traditional wired or wireless dumb doorbell, it's simpler.

But there are cases where server-side is difficult or impossible, especially if you want "smart" features like photos or routing or two-way interaction. Higher cost, permission from property owner if renting, etc.

Pushing the infrastructure to client-side solves these problems. Most users will have the client infrastructure in their pocket already. No wires. No new piece of hardware to maintain, repair, keep charged, etc.


You can get a wireless doorbell for $25 which will require no permission from any reasonable property owner.


But this gives you the functionality of a $200 system (Nest, Ring, etc) for ~zero cost, and not all property owners will approve a Nest camera on their porch.


The way I see it, Nest and Ring are a $20 doorbell, plus a $10 range extender so you can hear the bell if you're out the back, plus a $170 home CCTV system because you're in a high crime area.

Seems to me a QR code removes the $170 bit that was a key part of the Ring camera value proposition.


I'm in a very low (nonexistent, really) crime area and I like the camera on the doorbell. Not worried about anyone breaking in, but being able to tell at a glance whether it's a package, a neighbor, or a salesman ... that's valuable.


The "ring me even if I'm not at home" feature has some value also.

And for people who do not live in high-crime areas, but might want the other features of a Ring camera, the value distribution would necessarily be different.


I wasn't thinking camera. Just a doorbell.

https://www.honeywellstore.com/store/products/portable-wirel...


Any recommendations for a $25 wireless doorbell that actually works? I went through two of them and both stopped working after a year. The location they need to be installed in is slightly exposed to the elements and it seems cheap doorbells really don't like that.


No personal experience unfortunately. I have a brass antique reproduction twist bell!

I would look for something like this: https://www.honeywellstore.com/store/products/portable-wirel...


If I'm already holding my phone in my hand why wouldn't I just call you?


The pizza guy, your neighbor, and firefighters don't always have direct access to your phone number.


The pizza guy and firefighters are not going to scan a QR code on your door.


How is scenario 1 100% on the client side?


Bad metaphor perhaps. Attempted to clarify above.


Not to mention a QR code excludes many people such as children and the elderly who might not have phones


Good point, I'm hoping that this increases access rather than decrease it. In my neighborhood there are plenty of homes without doorbells.


Maybe those people don’t want people to bother them. I keep the buzzer in my apartment turned off a lot of the time because random people buzz it trying to deliver things to my neighbours. We have a concierge desk for that.


I think a note feature explaining why they are there would be useful.

Knocking or a physical doorbell noise is fine for my house. But if I’m not home, they have no way to communicate with me unless they leave a note on the door, which requires them to have paper and me to not be traveling for days.


I agree, I've missed this feature myself. I wonder if the QR could be your away doorbell, "Gone fishing, leave a message"


I don't want people to know when I am out of the house. It drives me crazy when solicitors leave ads on my door handle, b/c I can be out of town for weeks.


And not everyone carries a smartphone to scan QR code - read, elementary kids coming over every evening to play :)


Option 2 requires power, which not all doors have. There are wireless doorbells, but perhaps OP doesn't want to have to remember to charge or swap batteries.


While option 1 requires connectivity, which not all doors have. I live in a large apartment block. There is zero phone signal at my front door. WiFi, yes, but I’m not giving some random access to my WiFi network.


My app idea is to tell guests to "Connect to this SSID to knock", and have a way of scanning for new MACs on the network and notifying the door owner... /s

For security of course it'll be an SSID that doesn't connect to anything else, because hey, we care about security. ;-)

Another app is: "connect to this SSID and ping6 2345:0425:2CA1:0000:0000:0567:5673:23b5 to ring doorbell!".


This sounds far too simple for something as complex as dealing with unsolicited attendance notification injections occurring at randomly defined intervals against a primary public<>private security surface.

Particularly when you consider that some of those attendance injections may contain potential threats or unsolicited commercial messaging, or be designed to cause interference with predefined private processes, or even be designed just to consume processor cycles in unnecessary communication processing across the security layer.

While I like your implementation suggestion it feels a little lightweight for something this important. Please revisit the scope and come back with a more fully fleshed out project proposal.


Feedback: Bad UX. After scanning your example code I got page which asked me to take photo and I get really confused because I thought you want me to scan QR code again but there is no way to switch to other camera of my phone.

Overall this feels too complicated. Unfriendly to people without smartphone or mobile internet. I understand this is DIY equivalent of camera doorbell, but I would definitely prefer some no-name chinese radio doorbell both as one ringing and maintaining it.


Thanks for the feedback. I agree that the UX needs lots of improving - I'm wondering if more instructions on the QR code or the page for the doorbell would work better?

While a cheap radio doorbell might be better in many cases, there are still circumstances where it's not suitable. I'm trying to figure out which those are?


>I'm wondering if more instructions on the QR code or the page for the doorbell would work better?

In general you should display a prompt explaining why a permission is needed (eg. "we need access to your camera to camera to take a picture to send to the owner, click allow on the next screen to allow."), and only ask for permissions after the user accepts the first prompt.

However in this particular case you shouldn't have to request camera access directly. Using <input type="file" accept="image/*" capture="user> will display an system interface (ie. from the browser or OS) to allow the user to take/select an existing picture. It also already has preview and front/back camera selector built in, so you don't have to implement that yourself.

https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes...


If you're at the point of asking permissions, might as well grab the location data as well. You could then verify that the person hitting the QR code is actually on your front step which would eliminate all of the false positives like the replay attacks, copies being used in other locations, etc.


100% agree with explaining before asking permission.

I'll have a look at using the `capture` attribute on an input. My initial idea was to do video over webRTC, but the selfie version works okay for a first version


There are tons of cheap wireless units available that just use a bit of sticky tape to "install" the button to the door and then you can place the receiver/bell where ever you want. These work well and are much more understood by visitors.

Of course, you would not have learned your first iOS/Android app with that approach. Maybe that's the better lesson to learn though--not everything needs to be an app


So while I find that idea interesting, I would rather prefer knocking or texting on the doorstep of peoples homes.

I might have a situation where the QR Code makes sense though. I'm renting a location for a party at the top of a building, which is only accessible by transponder cards. So there is no door bell or anything. Instead of having someone letting the guests in, this could be an alternative.


Your house seems more welcoming with a QR code? Scanning it seems like a hassle for visitors. I'd probably just knock.


You'd knock? Depending on our relationship I'd just leave. Especially after being asked to take a photo - I already dislike video doorbells but sending a picture via an app where it will be stored for who knows how long is not something I'll go along with.


I answered assuming that the house belongs to a friend or loved one, or that I have some important reason I want the occupant's immediate attention. In those situations, I'd knock.

I do very strongly prefer a QR code thing to something like a Ring (as long as the QR code isn't going to a service such as Ring), though, but neither is better than knocking.


Dislike why?


I dislike them because the odds are overwhelming that they're sending the video off to some company I don't trust. I'm pretty averse to being spied on (especially by companies), even in relatively innocuous ways.

I don't like even being in neighborhoods where these things are in common use. Privacy issues aside, I take a prevalence of surveillance systems as an indication that the area they're in is an undesirable place to be. Either it's actually dangerous, or the people living in them think it's dangerous. Either way, that's a bad sign.


Hm. I think a lot of new homes (around me) have cameras. Just built with them by developer/etc.

I have cameras around the outside of my house. Not worried about crime (despite it seeming otherwise). I don't look at the video feed when people ring my doorbell.

Cameras have been helpful: - Someone accidentally backed into my house. Camera caught it. - Something was delivered that required my attention. Was able to walk back from another house to meet them (knowing they were at my door) - Check out branches/etc. falling on my cars during high wind


Interesting idea...

Cheap wireless doorbell is $5 delivered from Amazon. That's your biggest competition for the straightforward case. And that's easier to install, and easier to use.

There are plenty of scenarios where a Qr -> optional form -> notification is useful, eg hosting an event -- so maybe explore/emphasize those rather than the simple approach.

Fighting abuse and the resulting customer service, bad reviews, etc will be a constant drain/challenge.

There might be some market overlap with generic notification apps like Pushover.


I'm actually your target market here, but I want to replace my old exterior garage-door keypad with a (weather-protected) QR code. Same same, but text/twilio/home-assistant URL to allow me to trigger/confirm the garage door opening, probably IFTT.

Agree also with the "scan this code when you arrive to the party" => are you here? Y/N => notification. Pop a geo-permissions prompt and geo-fence "YES" in certain cases, and you're getting somewhere.


For your own garage door, if you are going to need your phone anyway to scan the code, why not just use regular automation tools? I.e. Just press a button on your home screen and you're done. Something like Home Assistant can do that easily enough.


It's the "external user" use case, and a case of the over-complicators gloves... instead of changing the 9v battery in that box every "$N" years, put a QR code up that gives you the regular pin pad thing and then triggers HA in the back end. (that's why I suggested "IFTTT" integration).

Obviously there's 100's of easier ways to manage things which is why I haven't done anything on it yet. It just seemed like an adjacent use-case worth sharing to the creator.

I'm not wiring up a "doorbell" to my back garage, but popping an "approve/deny" thing that eventually hits an API endpoint or IFTTT integration (with geo-location?) isn't that far off from what he has and is an entirely different value-prop of utility.


Why QR over NFC? NFC's tap-to-activate functionality is usually way faster than my camera app


..see my adjacent reply: it's the universality of access (kindof) that's tempting in replacing a physical keypad with a "virtual keypad". "Scan to enter => 1234 => Access Granted!"

Yeah, yeah, hackers, open API endpoints, DOS, rate limiting, etc., but it's an interesting use case: "Virtual Keypads" near doors.


Thanks, that's good feedback!


What's the advantage of this over a traditional doorbell + a phone (which everyone already has)? If I'm home, I can hear them. If I'm not, they can just message/call me.


I know it's situational, but going to a party where you don't have the host's number? Also in general if you want to be rung at a temp. location but not hand out your phone number? (e.g meetups at company premises where you only have a door bell at the wrong location)

I wouldn't call it a real replacement, but I can see a dozen uses.


Doorbell or knocking solves this? What are the other uses you can think of? Genuinely curious because I don't see them.


I've been to several meetups here where the company has larger offices in a high rise tower and e.g. the meetup is on the 4th floor but the door bell rings in the 3rd floor reception, and because it's after work, no one is there. People arrive in a 30min window, so someone would have to stand at the entrance, or put signs everywhere, or let people wait. As I said, situational, but "scan code to let someone's personal phone buzz and not have their personal phone number posted anywhere" works as one case.

The other one was a party at someone's apartment and I only had their IRC and twitter handle but not their phone number, and they had a key pad at the entrance (long story, not their fault) and I didn't have the number. And yes, I tried to ping them but they seemed to ignore their phone so I had to wait for other guests to arrive anyway.

My third example would be temporary event locations where there simply is no door bell or the organizers are not where it would ring and again, a phone works but it would leak the caller's number and the organizer's number whereas I suppose you can just uninstall the app or have different URLs generated that stop buzzing after a while.

Situational, as I said.


1 & 3 seem reasonable applications for this, but I don't see it as a replacement for a doorbell. 2 seems just like a minor organisational blunder.


> going to a party where you don't have the host's number

What? Door bells worked before phones existed.


See my sibling comment, not all apartments have accessible door bells.


Don't all apartments have an intercom? I suppose I just assumed they did.


Larger buildings with many units usually do have intercoms with two-way audio (and sometimes one-way video) and the ability for the resident to remotely unlock the door. Sometimes these work via telephone or Internet, so the resident does not even have to be home.

Smaller buildings with just a few units usually just have simple dumb wired doorbells. And they are usually not broken.

Different cities/neighborhoods have a different mix of larger and smaller buildings.

This QR code idea is interesting, because it lets you go from dumb to smart, bypassing all of the steps that would normally be necessary (cost, approval, installation, maintenance, etc).

It's not as "good" as Nest etc, but it gets you most of the way there for almost none of the hassle.

Not for me, probably, but interesting.


Traditional doorbell needs an electrically powered button on the exterior. Phone needs visitor to have your private contact info or you would need to publicly add a note with that to your door.


There are battery powered remote doorbell buttons. Eg, $29 at Ace Hardware, with a 100 foot range - https://www.acehardware.com/departments/hardware/safety-and-... .

Also, a real traditional doorbell is mechanically coupled to the bell, with no electricity at all.


QR solution needs the visitor to (a) have a smartphone with charged battery and (b) Internet connectivity. Quite common, but wont work for everybody.


Grandma delivering cookies is out of luck. To be fair, if you don't have a phone you could just knock. But then you could just knock to begin with.


If you don't want to use electricity, you can have a knock.

What reason would you want to be notified of unknown visitors knocking on your doors when you're away? The only people I can see fitting this description are delivery drivers & salesmen?

Further, what if you're home and your phone is in another room, is on silent, or is dead?

What is you have a spouse or housemate? Do both of you get notified?

And there's also a subset of people who get frustrated by having to use QR codes in restaurants, who I suspect would be equally frustrated by this.


I have a few ideas about this,

One thing I've found useful so far is that the notification sound is different from my phone/message chime, so when I hear it I know it's someone at the door.

I'm curious to hear what other people think?


This feels like a mocking app of today's Reddit post requiring an app to operate an elevator.

Kinda silly in any case. If you want to use a QR, just point it to your phone number so I can call you and talk to you.


I can see some potential for people with hearing loss. I've seen apartments and houses of such folks, with some small dedicated bulbs or even normal ceiling lights flashing furiously on all over the house upon someone ringing the doorbell. A doorbell signaling smartphones, making smart wrist watches vibrate etc, could be reasonable in such cases. But it could be still a plain uncomplicated button next to the door.


A "smart" doorbell that can notify you in various ways makes sense - even without hearing loss you may not always be able to hear the doorbell (headphones).

Expecting guests and random strangers to go out of their way to accomodate that is not ideal. I don't know how I would react if I had to scan a QR code to ring a doorbell but chances are I would leave.


Thanks, I haven't heard that perspective before.



Reading through the comments I realize the subheading on the site is not sending the right message:

> Replace your doorbell with a QR code

The purpose of the app is to create a doorbell for instances/contexts where there isn't one. Not to replace currently working doorbells.


Knock? Even if there is a doorbell, I prefer to knock as it's less disruptive.


"Print out your own virtual doorbell!"


You're focusing on an app, instead of ringing person's UX and _the_ doorbell itself.

My suggestion: find a niche, like a doorbell for hearing impaired home owners. Otherwise you'll be recreating Nest. Google won't buy identical product twice, to kill it. A generic Nest-like product has little chances to take over the market.

A button feels more natural and is much more approachable over an QR code. QR may be a nice fail-over for when no one is opening the door in reaction to knocking or pushing a button. But QR as the main method? Maybe for evolving markets or harsh neighborhoods where wireless doorbells get stolen - if that's even a thing.

You're looking into providing value to home-owners, by making it easier for someone outside their homes. In most cases this dumb button that makes some sound inside the house just works. Little area for improvement here, for most people.

Your potential market for people willing to stick a QR code on their door are:

> "I'm hearing-impaired. Please use below QR code if I don't hear you knock"

> "I'm not opening? chat with me here [QR code]"

↑ this is your potential target. You already see that most comments in this thread tell you that people don't want QR codes on their doors. You have an idea for a solution still looking for a problem. Accessibility around hearing loss may be one.

You can help people. And from a business perspective, you may be able to get government grants for such project, which may be better for you than crowd-sourcing. And, you may get customers who get their purchases partially covered by gov health programs, if you properly interact with related accessibility-related gov bodies (YMMV around the world of course), apply for getting your stuff assessed for free advertisements inside hearing loss-related clinics etc. And again - you can make a product that makes impaired folks' lives better. Win-win.

There are multiple ESP32-based doorbell projects (I like this one[0]) that can be expanded easily with code changes. I can't really see how a QR code is better. Make your product either equally interesting to public or covering some niche use-case. And again: Nest...

[0] https://tristam.ie/2023/758/


I recently visited a friend in Finland. In Finland it's common for apartments to not have doorbells downstairs. Instead the door has a pincode that people use to get in which are typically shared with friends when you invite them.

Except those pin codes are now commonly disabled for security reasons. So, I was waiting downstairs wondering what to do and in the end just called my friend after which he came downstairs to open the door. That works of course but a QR code would be a good alternative.

Even if it just contained a tel:// link with the phone number. I love QR codes for low tech solutions like this.

This stuff doesn't have to be hard. And you don't even need an app for this. Just print your own code with your phone number, email address, etc. (from any of a vast number of web based generators) and put it near the door with some instructions.


Is there a captcha, or can people ding-dong-ditch you from a continent apart?


This is a good feature enhancement, to check the location of the ding-donging party.


Though since it's trivial spoofed I don't know why you'd bother.

Something like this really needs a periodic refresh or some proximity proof like NFC.


At this point just knock!


We're willing to offer a $7M seed at a $50M valuation for your knock technology.


Something something Knockchain


Only if you knock technology uses AI :)


And only if by "uses AI" you say it has AI inside the hardware but really it's a network-enabled thin client that calls out to a server wrapping GPT calls.


Crazy the doorbell replaced knocking and now the internet is replacing doorbells.

Who invented doors? Perhaps that’s where it all went wrong. /s


Right now you can ding dong ditch if you have the code. As others mentioned using location could help. Or maybe a one-time-pin?


Honestly, for serious use - yes, but there is a fun aspect to the app. Have a friend or remote partner print the code, and ring a doorbell when they want to get in touch, or just as a reminder they'rethinking of you? Like a message, but without the 'baggage'


On early-days facebook you could "poke" someone. Like a virtual empty message, it had no meaning or "baggage" linked to it, other than that the poke-er was thinking of the poke-ee at that moment.

About a decade before that, we kids basically only had SMS text messaging, and it was very expensive in my country, mobile data doubly so. There was however a "please call me" feature, where you could send a "please call me" text to a friend free of charge. We used to send please call me's to one another all the time, not because we wanted to be called, it was just the cheapest form of digital communication.


The poke feature is back! It was re-introduced this year some time.


Nice work!

I wonder if instead of complexity you should call this a cheaper alternative to a smart doorbell?

I don't think many of us think of smart doorbells as particularly complex. However, they could be out of budget for many.

Alternatively, you could market as privacy respecting, where a smart doorbell is always recording.


Thank you! Those are good points. I'm still trying to figure out what the differentiating factor is for other people. For me it's the ease with which I can replace a QR and receiving a notification even when I'm not home


As a hack, this is great. As a thing I would actually use? Very, very unlikely.

- I would never use a random QR code in public and I wouldn’t ask anyone else to.

- Pranking seems like an issue.

- If I know someone, they’ll text me they’ve arrived. If I don’t know someone, there are two main cases: delivery person, who is going to pound the door and leave immediately (and I’ll get a notification of delivery); and religious proselytizers, political door-knockers, and solar company sales people, none of whom I care remotely about talking to.

Again, as a project, this is delightful. But as a thing to incorporate into my home, I can’t see the use case.

EDIT: Also, criminals. They’re not going to use a QR code to see if I’m home.


I went down a rabbit hole several years ago with this concept.

I built much of the code front end and back end then abandoned it because I just could not summon the belief in the idea as a startup.

I was focused on QR codes as entry points to buildings and companies, with integrated guest book functionality.

This was pre-covid so QR codes had not yet become something everyone knew how to drive and mobile phone implementation was not yet universal.

Also being pre-covid every still went to the office to go to work.

I came up with many names and registered many domains I think one of them was paperdoorbell.com and many other such variants.


My old fantasy of "scan an NFC tag and it brings up an UI on your phone to do things to the machine bearing the tag" applies here too.

Easily add a control panel to machines that can't easily have one (because of cost etc). Or a debugging panel for improved UX over the usual "three LEDs giving you a code you have to look up in the user manual".

NFC is better UX (less user taps).

For an easy PoC, make an NFC tag that connects you to an SSID and opens the captive portal usually used for Wi-Fi auth as the control panel.


I thought about keeping my existing doorbell button and chime, but adding an ESP32 plus hall effect sensor, to detect when the doorbell chime is being powered and trigger a notification over wifi.

It seems a bit convoluted, though. Is there a DPST momentary button I can use instead (removing the need for the hall effect sensor)? I searched on digikey but 'DPST momentary' came back with results that were too bare (just the button), expensive ($50 per unit) and had a long lead time (8 weeks).


Why would you use a hall effect sensor at all, or a dpst for that matter? You just need two resistors.

Just tap the dc leg between the bell and the chime into a voltage divider - for a 16V doorbell to a 3.3V esp32 io pin, r1=15k and r2=3.3k is exact - and you're done.


How common is DC in home doorbell systems? Most doorbell wiring diagrams I've seen in the US show systems that appear to be all AC.


Thanks. This makes much more sense.


It has been a while since a _useful_ new app came along! Thank you, i appreciate it to the point I'd be willing to pay for it.

Feedback: Teach people to never ever scan a QR code if they don't know for a fact who created it. For if you don't, you'll be part of the crowd who is conditioning people to scan all the QR codes they can find without thinking...


I'm hoping this is satire because if not it is legitimately one of the worst ideas I have seen.


I don’t see this as a doorbell, I see it as a QR code that can be trivially reproduced and used to trigger notifications on your phone by anyone from anywhere at any time, basically completely anonymously. Not a great idea.


The one thing I do not appreciate about this Show HN is that there is no repo linked. I do NOT want to install any apps, I just want to build something like this without becoming someone's customer...

I guess my implementation would just be sending a notification to my phone on a messaging platform, or send an email. Maybe use https://ntfy.sh and the more generic app to get these notifications.


My first reaction too was, hey I could do this with ntfy.sh


I think I walked past this in a European capital city, could that have been your doorbell (city not specified for obvious reasons)? Or are other people already using this?


I doubt that it was one of mine, I'm much further south.

I'd be very curious to hear more about it



Good for you that you build your first mobile app(s) and for having an inventive mind, but please be aware that there are many many "bad" people out there that will abuse/prank/exploit simple ideas like yours. Keep yourself safe and don't allow people to disturb you in ways you haven't imagined. Unfortunately this is the state of the world right now :-(


Thanks for you concern. I need to look into different safeguards to prevent abuse. Right now I'm trying to see if there is at least some use


I’m sorry. I’m just frustrated enough scanning the QR code in the restaurant.

Now I have to scan another QR code just to meet you?

I prefer looking for new friends.


if you improve the UX on this thing I think im not a businessmen but i think you would be competing against 'Ring'


I love this sort of thing, very cool idea. I think it makes for a great weekend project to implement something similar yourself.


Agreed, if you're into hacking your own doorbell, there are a lot of really cool examples online of projects people have done.

I'm considering setting up an ESP to integrate my old bell's chime with the QR code.


Now someone might want to check for neighbors having such QR codes on their doors and replace them with QR serving ads (and accessorily ring the "bell" application), or just with something unrelated (like a page to install a rogue app).

On a side note, a delivery person might actually not want to scan the QR code because (a) if you do this all the day long, it take much more time than pushing doorbell buttons, and (b) if they use their professional devices to do this, they might either have that URL blocked, or scanning a "random" QR code might be against their company's policies because it might expose them to security risks (imagine a phishing page with the login interface of the delivery company, or a site serving malware).


It made me immediately think of the sign in and sign out QR code for my kid's preschool haha. Interesting idea!


iOS debuted a feature called “App Clips” awhile ago (2020?) that would be perfect for this.

Most phones have an NFC reader as well so should work with Android too.

Similar concept:

1) person taps phone against “door bell”

2) sends notification to user(s)

3) optionally, send “selfie”

IIRC, app clips needed to be very small in size. So something like this could work, even in low bandwidth situations (ie, poor signal strength)


Thanks for the suggestion! I understood "app clips" to be like notifications, but sounds like they are worth looking into.


Nfc touch doorbell would also be cool. Though, I do feel it's too technically advanced for most people to use.


That would be cool - the QR could also be a RFID tag. But like you mention, that would also be more advanced


I have a better idea: using a QR code as your door key.

* Install a lock that does not have any external mechanism to unlock it. No key holes, no password pad, nothing. So there will be no lock picking in any way.

* Use your peep hole as a camera.

* Show a QR code to said camera.

* Door unlocks if QR code is correct.


What's the failsafe mode? (e.g. battery is dead, mechanism fails, etc.)


Kicking the door in is surprisingly easy in the US where most doors are framed in soft pine, if that does not work an angle grinder and a sufficient supply of discs can (eventually) cut through anything.


That seems like a very expensive repair following a failure.


In theory, if you don't lose your key, locks work indefinitely.

Battery-powered locks.. well.. they die a lot more than 0 times


what is the failsafe mode if you lost all your keys, or forget your password, or fingerprint reader runs out of battery? same thing applies here.


With a typical smart lock, the failsafe mode for the battery dying or forgetting your password is a backup key.

The failsafe mode for losing a backup key is getting a locksmith to come out and fashion you a new key.


if a locksmith can open your door, others can, too. in this rare event, i think brute force is an acceptable price to pay for the extra security.


It doesn't really matter whether a locksmith can open your door. With an angle grinder and some patience, anyone can open practically any residential door (as noted by another commenter). The question then simply becomes how expensive it will be to repair everything afterwards -- and all because the battery ran out.


Sounds like a cool and novel idea. But I can imagine this becoming a remote version of that knock-door-and-run game - ding dong dash!

Wish you the best with it though. Could catch on


I unwired my doorbell and never looked back. It’s been one of the best decisions I’ve made about my house. If you get past the FOMO you might love it too. Why does the world get an interrupt button for your home?


A doorbell is just an easier and more polite version of knocking on your door. Do you also do something to prevent people from knocking on your door (e.g. a pit trap in front of it)?


Probably the same thing I did, left the button. It's a lot more peaceful not having random people bother me at home.


Where do you live that random strangers are bothering you? I've lived in a few cities but this was never a problem.


Yeah but there’s a slide down to the ball pit.


That sounds fun. Any problems with it filling up on Halloween or do you just empty it often?


There's a "Complaints" button that opens another trap door to another ball pit. It's actually ball pits all the way down (though to be perfectly honest I haven't tested). What's important is that I haven't received a single complaint.


Visitors?


Absolutely unhinged(based)


I would want a NFC one tbh.


What would that really look like?? People need to have something in advance to ring your bell?


Rather use NFC TAG, INSTEAD SCANNING QR REQUIRES SPECIFIC APP, HELL EVEN IN 2024 I DONT KNOW HOW TO SCAN QR WITHOUT 3RD PARTY APP, AND I HAVE GOOGLE LENS AND RELATED APPS DISABLED


Click the Camera app, then point at the QR code and press the link


This is a brilliant idea! Love the "take a photo" at the start. I assume (if you answer) it will go through WebRTC?

Might be nice to play a "ding dong" sound in the browser?


Currently it isn't doing WebRTC, but that is the idea. Although I'm not sure if I want to add audio and/or video?


I wish my annoying neighbor would get this, because then I can post the code online and have the whole world knocking on his door at all hours of the day.


Why does this need an app? Why not just send me a text, or better, yet just an SMSTO link? (ie SMSTO:+1123456:Open the door!)


this seems silly

seeing as you need an internet connection to access whether the doorbell has been rung, you may as well connect a physical doorbell to an app that monitors this and gives you a notification on your phone without the need for a QR code

the QR code is just a hassle


I know this won’t enrich the conversation much, but here’s a Reddit link to the comments showing “normal folk” reactions to a QR code on a door.

https://reddit.nerdvpn.de/r/mildlyinfuriating/comments/1gg37...


The bubble you live in that makes you think this is a good idea. Sheesh.


Also there are rfid based smart stickers with microconteoplers abailable


"R2-D2 you know better than to trust a strange QR code".

Scanning QR codes outside a trusted environment (e.g. a workplace stock keeping system) is asking for trouble. Security advice now routinely recommends not deploying QR codes on your products, nor encouraging your employees/users to scan strange codes.

It's like 1995 all over again.

EDIT: In response to doubters below https://www.bbc.co.uk/news/articles/cz472gy8nd9o

Besides, to paraphrase Dubya: "Goatse me once, shame on...shame on you. Goatse me—you can't get goastsie'd again."


The risk is exactly the same as clicking on a link on the internet. There is no additional risk. You could type the link in your browser manually after decoding and the exact same thing would happen. That's because most QR codes are simple links. The ones that aren't are things like cards, wifi credentials, etc. But most of them are links. You click on them by scanning them. The same mechanisms that make using the internet a mostly safe experience that billions of people enjoy on a daily bases, also apply to qr codes. Because it's the exact same browser that opens them.

So, use common sense here. Links and QR codes are everywhere. And people click or scan them all the time at their own discretion.

This is not like 1995 all over again. All the same protection mechanisms that we've put up since then for links also work for QR codes. There's no real difference between a link I email you and a QR code that you encounter in the wild. You click or scan them and a browser opens and does its thing. I mention email here because email clients typically don't really restrict what you can do with links in them. There's a reason for that: people send a lot of links via email and links are useful. So the fact that some bad actors send people evil links via spam, is not enough reason to disable the feature.

QR codes are just a way to provide links for people to "click". It's not even a new way because they've been around for quite long. The US and Europe are late to this party. Most of the rest of the world already runs on QR codes for quite some time. Especially places like China and Japan.

Ps. I run a company that uses QR codes a lot. They solve a lot of issues for us. IMHO they are severely underused currently.


Why do I hear this so often? Isn’t the risk exactly the same as clicking random links on the internet? Do you do a background check before opening an external link to a story on hacker news? The risk is exactly the same as when you scan a random QR code.


You can hover over a link to see the destination, this isn’t always possible with a qr code as it depends on the client app


How many people actually hover/long press every link before clicking, especially on sites with UGC that allow for link spoofing (eg. <a href="http://evil.example">http://site.example</a>)? If you're paranoid to do that, you can probably figure out how to audit qr codes before opening them. On iOS it's trivial to make one in Shortcuts. On Android, Firefox confirms the link before opening.


If the native tooling always confirmed a qr code then I think you’d be right. Until then it’s security practices not paranoia.


And what does that tell you? How do you detect malware from the URL? Do you have a whitelist of known-good domains and don’t visit anything else?


The http protocol uses human readable addresses for a reason.


Yes, to make addresses memorable, not to detect malicious hosts. If I give you a random .com-domain, how do you determine wether it is safe? And do you actually do it if it’s the link of a hacker news post, for example?


Qrs may have other data, not only links, and there is always the extra (but minimal) risk of a vulnerability in the qr reader itself.

Other than that, it's the same as clicking a link on an email, yes.


Can you provide a source for that? I have never heard that before and it seems ridiculous to me. The advice connected to QR codes I suggest is to not make the reader app auto-visit decoded links, but just show decoded content.


That is a valid concern, you are not the only person to have raised this.


Sorry, that's utter bobbins.

QR codes can contain a limited set of data. There's no possibility of a buffer-overflow or malicious program.

Every QR reader I've seen shows you the destination before taking you there.

It might be a scam website - but that's no different to seeing an poster and manually typing in the address.

Yes, QR codes can contain an auto-generated email or premium SMS. But they won't send automatically. The user remains in control.


> It might be a scam website - but that's no different to seeing an poster and manually typing in the address.

Disagree, because:

* QR codes are opaque to humans. You can't visually tell if one is legit or not.

* QR codes often use URL shorteners, so that the URL contained is just https://exam.ple/4pTF6x4M9 is not unusual.

Someone can replace a QR code with a sticker overlay and link to a phishing site. Replacing a URL on a poster is also possible, of course, but harder to make look convincing in the first place and significantly simpler to detect.


* Printed URls are also opaque. How do you know if the correct website is whatever .com or whatever .org?

* Printed URls often contain shortened links.

I'd argue that most QR sticker overlays are also pretty inept. See a sample at https://shkspr.mobi/blog/2024/07/qr-code-hijacking-attempts-...


> QR codes can contain a limited set of data. There's no possibility of a buffer-overflow or malicious program.

Source?



Rather use NFC TAG,


>Having a doorbell does not need to be complicated.

I'm not sure if your and my definition of complicated are the same in this case


That was my exact first thought. That seems to be a lot more complicated than a traditional bell, except for the fact that you don't have to run two wires there (a thing most places will already have there).

I mean this could be a okay solution for a very certain set of circumstances, but making your visitors scan a QR-Code seems like bad UX, why not have them fill out a form while you're at it?

If I had a situation where it was impossible to run wires through the wall I'd install a old-school knocker on the door and a knock sensor on the inside. UX is intuitive and the knock sensor can still send me things to the phone if I like that.


> If I had a situation where it was impossible to run wires through the wall ...

Wireless doorbells can be found for tens of dollars. You can get them with multiple receivers you can place around your house.


We have a 40 yard driveway up a hill and trees in the line of sight. I am going to try this, as it will add another option of contacting us.


True. What are you comparing it to if I may ask - a traditional doorbell or a modern smart doorbell?


The user interface for a doorbell (smart or dumb) is a a single button that you press, with your finger. Compare that to take out my phone, find a way to scan a qr code, scan it, install an app (?!?!), press a single button with my finger, on the app.

This is even supposing that I want to do that to begin with (I know for sure delivery drivers are never doing it).

Good job on the project, I really mean it. It doesn't matter what you do, it matters that you've achieved it and for that, congrats. But as a practical semi-object, this has to be one of the worst ways possible to solve the problem.


That is a valid point. The visitor does not need to install the app, but it's still more complicated than pushing a button.

From the owner's perspective I imagine it's at least a little bit simpler to install an app and put up a QR code. Although if they have to print it out themselves I guess all bets are off.

> Good job on the project, I really mean it. It doesn't matter what you do, it matters that you've achieved it and for that, congrats. But as a practical semi-object, this has to be one of the worst ways possible to solve the problem.

Thank you, those are kind words. I doubt that this is the worst possible way in every context, but working towards better solutions is why we share stuff and ask/give feedback :)


A knock.


Just curious, what does a "modern smart doorbell" do exactly?


Typically transmit video to phones, which is also pretty trivial with about $20 of hardware.


A text or call on said smartphone.




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: