
Show HN: CallStop – Superhuman for your phone number - davidajackson
Robocalls and unwanted calls are one of the biggest hassles these days. Over 50% of phone traffic is spam.<p>I&#x27;m the founder of CallStop: <a href="https:&#x2F;&#x2F;apps.apple.com&#x2F;us&#x2F;app&#x2F;callstop&#x2F;id1455892856" rel="nofollow">https:&#x2F;&#x2F;apps.apple.com&#x2F;us&#x2F;app&#x2F;callstop&#x2F;id1455892856</a><p>CallStop allows you to:<p>- Block 100% of robocalls on your current number, using your contacts as a whitelist<p>- Effortlessly email call invites to an any email (that can be joined in one tap, the PIN is embedded), where the recipient can only call you starting 5 minutes before the meeting start and up until 5 minutes after the meeting end<p>- Pause call filtering and have it automatically resume after a certain time<p>- Accept whitelist requests to join your whitelist, and receive notes from the callers prior to accepting<p>- Specify PINs you can give to loved ones or groups to reach you from unknown numbers.<p>- Get a second phone number with which you can give out in lieu of your primary.<p>CallStop is a productivity tool that lets you better manage your time and who can reach you.<p>If you&#x27;re expecting a call from a business from an unknown number, or want to limit a salesperson from calling you more than once, CallStop is perfect for managing these interactions.
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nlh
Congrats on launching!

One security-related question: I had looked into this area previously as a
user and a security-conscious friend pointed out that systems that use call
forwarding to stop the spam problem are a HUGE security risk.

You’re effectively man-in-the-middling all mobile calls, SMS, etc, and if
there’s some sort of compromise (or, much less likely, malicious act) on your
end, all of us users will be in a tough spot.

Is this accurate? Can you share some thoughts?

(Not trying to knock your business or approach, btw - just want to know if the
fears are founded or not.)

~~~
runako
Same thought here. I have been toying with the idea of building something OSS
so that people could run it themselves, for this reason.

(Also I have what is possibly a common filtering case in the US that would
eliminate 95% of my spam calls without blocking any relevant calls from "new"
numbers. And for whatever reason, I have not seen it implemented anywhere
yet.)

~~~
nlh
IF (area code == my area code) AND (prefix == my prefix) AND (last 4 != my
last 4) THEN SPAM SPAM SPAM ?

~~~
runako
YES

Also: if (area code == my area code) AND (number NOT IN whitelist)

Basically: I have a mobile number in an area I left 15 years ago. Any call I
get from there that's not one of my friends is de facto spam.

~~~
SandyAndyPerth
>I have a mobile number in an area

Wow, that's fascinating to find out that is how the US works.

Australian mobile numbers and I'm pretty sure most of the European ones, are
prefixed by carrier and have no geographical breakdown.

~~~
runako
Yup, the first 3 digits (the area code) tell you the the part of the country
where the number is located. Obviously this was setup before mobile!

> prefixed by carrier and have no geographical breakdown.

I'm not sure how/if that would work here given the active mergers &
acquisitions in telecom. (Among other things, some of these require some
customers to be divested to achieve approval of the deal.)

Additionally, we actually had Congress pass a law requiring the ability for
consumers to take their number to other carriers:

[https://en.wikipedia.org/wiki/North_American_Numbering_Plan#...](https://en.wikipedia.org/wiki/North_American_Numbering_Plan#Number_portability)

Prior to this, carriers could use as leverage the fact that people prefer not
to change their phone number.

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sm4rk0
_Over 50% of phone traffic is spam._

Please, don't generalize. That statistic is maybe valid in the USA. In my case
(Serbia) spam is practically 0%. There's an occasional landline call or two
per month but that's enough for making fun by letting our kids answer the
phone and troll the spammers. Third world "problems" (:

Anyway, I support your fight against spammers.

~~~
bestouff
Same thing in France. I wonder if phone spam exists elsewhere than in USA (in
UK perhaps) ?

~~~
leokennis
In the Netherlands, I get called unsolicited and for marketing purposes maybe
once a month. The call is always by a human, I’ve never been called by a
robot.

As soon as I notice it’s a marketing call I just hang up and if it’s not a
hidden number, I add it to my “blocked numbers” contact, which I have blocked
from incoming calls on my iPhone.

~~~
martin_a
You could also GDPR the shit out of them... ;-)

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jeremyw
I built a whitelisting phone system for my aging dad with Twilio, an OBi200
VoIP adapter, and gcloud for transcribing untrusted calls sent to voicemail.

(US specific) If you think the aggressive IRS and Sheriff scams are bad --
you've committed a crime only $100 _right now_ will solve! -- the shakedowns
targeting enfeebled senior citizens are truly sinister.

Which is to say, people who care for seniors (children of, part time
caregivers, etc) are an unserved audience for tools like yours. I would have
paid for one had it existed.

~~~
davidajackson
Good to hear, it's sad to see grandparents/parents get scammed. I've had a few
senior citizens getting these types of scams use CallStop to protect their
cell and landline. It feels good to be helping them.

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martin_a
People! You really need to get into politics or whatever and fix those things
from a legal side!

You really need to stop inventing services and starting businesses for the
most simple things in life!

edit: Don't get me wrong, I love the spirit, but there are _real_ problems to
tackle and you are still working on stopping telephone spam? It's 2020, nobody
should even think about things like that...

~~~
davidajackson
Robocalls are the #1 complaint to the FCC.

~~~
martin_a
Ok, then go out, complain to your local politicians and whom else in charge to
make a law to stop it. That's how it works.

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ascar
The problem I have with a whitlisting approach is, what if it's actually some
legitimate and damn important call? When my father was in the hospital close
to death I got informed by phone from an unknown number. You get these calls
hopefully only a few times in your lifetime, but I definitely don't want to
miss them.

What's your approach for these cases?

~~~
davidajackson
Most people don't answer unknown calls anymore. They're likely to miss these
life/death calls right now. That's why the PIN feature is better for most
people--you can give a 5 digit PIN to loved ones. You may be an exception if
you answer every call--I won't answer any call from an unknown number, and
most young people don't answer unknown calls anymore. Seniors tend to answer
more, but that's because they are more used to landlines and times when there
were less robocalls. I'd rather make sure that my family can remember a 5
digit PIN (obviously there are lots of tricks to make numbers memorable) than
answer every unknown call in my life.

~~~
wrs
Until this service becomes so popular that the robocallers start deliberately
working around it, I think you may only need a 1-digit PIN. I've had a service
from the phone company on my landline for decades that just makes an unknown
caller dial a 1 before my phone will ring, and it continues to nearly
eliminate spam calls. So the 1-digit PIN can just be a "1".

~~~
davidajackson
Randomized "Enter X to be connected" with 0-9 is a feature several people have
requested. I agree that you can probably cut most with just that.

~~~
RL_Quine
So, a captcha :)

~~~
moralestapia
A soundcha ?

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pavel_lishin
I want something different.

I want a Lenny, but that I don't have to conference in. That step is failure
prone, takes time, and usually doesn't work -by the time Lenny is on the line,
the spammer has long fucked off.

I want a "bot" that spews nonsense - but sufficiently plausible nonsense to
keep spammers on the line - that I can activate with a single button click, at
any point during a phone conversation with anyone. Either by reaching out to a
remote server, or by running it locally on my phone.

When a human being reaches my phone, I want to be able to keep them from
reaching others, for at least some time.

( Lenny: [https://toao.net/595-lenny](https://toao.net/595-lenny) )

~~~
offtotheraces
Check out the Robokiller app - their answerbots do exactly what you described.

[https://apps.apple.com/us/app/robokiller-block-spam-
calls/id...](https://apps.apple.com/us/app/robokiller-block-spam-
calls/id1022831885)

~~~
pavel_lishin
I tried - it might work like that on iPhone, but on Android you have to enable
some network-specific features that Google Fi doesn't currently support :(

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chadwittman
I really wish this would have come out like 4 years ago. I love the idea, but
Apple's newest iOS helped significantly cut down on the robocall annoyance.
I'm cheering for you!

~~~
davidajackson
Thank you, I'm definitely looking to continue working on productivity features
like scheduling to keep it relevant and less "platform vulnerable" so that it
can't made moot by Apple.

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bawolff
Interesting.

I kind of wish there was like an audio captcha app. If the number isnt in your
contacts, voice comes on asking them to type some random 4 digit number. Well
it is of course anarms race, almost all my call spam is recordings so i think
itd be effective.

~~~
davidajackson
A few people have mentioned they'd like this service, where a random
digit/puzzle is presented. I decided to focus on people who wanted the most
extreme call blocking service but would like to come back to this later.

~~~
procombo
Whitelists works fine. Pin "extensions" work fine. The next step is probably
just a simple question/answer regarding personal information about the
recipient.

Just like account security questions. Provide drop down selector/s for users
to select their question.

I'm not going to provide my public number here, but if a caller of mine isn't
whitelisted I just prompt them for my billing zip code. Now, that's not going
to work for every one, but considering who _I_ want to get phone calls from,
it's pretty foolproof.

Keep the energy up @davidajackson. I'd love to see you hugely successful with
your efforts!

------
ThomPete
Congrats on the launch.

My advice is to stay away from the "Like X for your Y". Define your own
category otherwise, you will end up just copying way too much of Superhumans
thinking.

~~~
davidajackson
I definitely will need a non-analogy description. I've called it a "Call
Manager" on the App Store. I'll see if I can think of something more...
descriptive.

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mehrdadn
Question: does any app (yours or others) block such calls in a manner that
prevents them from ringing at _all_? It's extremely frustrating for me when I
use a call blocking app only to find that it still rings for a split second
before suppressing afterward, and I have no clue why that happens with every
app.

~~~
soared
iOS has a setting to send numbers not in your contact direct to voicemail and
those never ring.

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soared
I would’ve loved this prior to getting a new iPhone, but from my perspective
the iOS setting that sends numbers not in your contact straight to voicemail
does 90% of what I’d use this service for.

You obviously have some useful features though (I do miss calls on occasion).

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hedora
I like the idea of having a pin.

I wonder if overloading the “extension” field in existing address books would
be reasonably ergonomic. Eg:

(555) 876-5309 ext 1337

Or similar syntax should work with legacy systems to share your phone number
(and maybe autodial the pin).

~~~
davidajackson
The format for autodialing with CallStop is "<number>,2,<PIN>". The commas are
pauses. You can store these in Apple contacts for example if you want to try
dialing a number, pausing, and then pressing a tone.

Here's what the PIN email invites look like, which use this system:

David Jackson has scheduled a call with you. To join, tap here:
11111111111,2,73827

Call start: Saturday, February 1, 2020 at 7:00:00 AM Pacific Standard Time

Call end: Saturday, February 1, 2020 at 8:00:00 AM Pacific Standard Time

You will be able to call David Jackson starting 5 minutes before the scheduled
time and until 5 minutes after. You can continue talking after the scheduled
end time, but you can only call David Jackson during this window of time.

If you're unable to join via the link above, call 1111111111, wait for the
prompt and then press 2, and enter the PIN 73827. Your call will then be
forwarded to David Jackson.

Organizer notes: None.

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colbertw08
Congrats, definitely going to give this a try as I get spam calls all day
long!

I wanted to tinker around with other phone projects what provider are you
using on the backend if you don’t mind sharing ?

~~~
davidajackson
Let me know how you like the app! The backend uses Twilio. They have good
documentation and examples, and their teams are responsive.

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Shank
Does it work with Google Voice forwarding? I tested it by calling my Google
Voice number, but it looks like it doesn't.

~~~
davidajackson
You can protect any number (cell, landline, google voice number) by forwarding
that number to your CallStop number. As long as you can forward the number to
CallStop, you can screen calls in this fashion. If you're intending to route
incoming calls from your CallStop number to another number, let me know and I
can try to add that option into the app. Also my email is david@callstop.com
if I can help any further.

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davidtranjs
Great tools. I am just a normal web developer, yet still receive unwanted
calls from the insurance sale every month

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winrid
So it's like a shared and community driven (but automatic) blacklist?

Do numbers ever need to get whitelisted?

~~~
davidajackson
CallStop uses whitelists that each person manages. When an unknown caller
calls you, they hear, "You have reached a phone number protected by CallStop.
If you know this person, press 1 to send a whitelist request with a quick
note. If you have a PIN to reach this person directly, press 2 and enter the
PIN." Your contacts are your default whitelist to begin.

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armatav
I thought CallKit only allows a blacklist of numbers to block, not a
whitelist.

~~~
davidajackson
Numbers forwarding means you can create whitelists. CallKit doesn't support
whitelisting as you mention. Whitelisting with CallKit was the first thing I
looked for in the Apple developer docs, and there was nothing on it, so I used
number forwarding.

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AgentK20
Any plans for Android? Would happily pay for a service like this.

~~~
mceachen
Android's built-in "do not disturb" setting supports silencing all phone calls
from numbers not in your address book.

~~~
dangoor
iOS supports this too: [https://support.apple.com/en-
us/HT207099](https://support.apple.com/en-us/HT207099)

