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Show HN: I made a macOS app to let me draw on the screen while on video calls (apps.apple.com)
232 points by rampatra on April 21, 2020 | hide | past | favorite | 92 comments

This is my first macOS app that I launched yesterday. Really excited to share it with you all. The app is called Presentify and it lets you better explain yourself during presentations or while working from home via video calls, etc. Given that most of us are now working from home, I thought this might be helpful to some.

Here are the links:

* Website: https://presentify.compzets.com

* Demo: https://youtu.be/CTR1iAbGhjg

* Mac App Store: https://apps.apple.com/app/presentify/id1507246666

Please, feel free to share your feedback. It would mean a lot to me.

Cool idea! Since you're asking for feedback, here's my question:

Is it drawing inside of the window, or is it at a fixed point on the screen? As in, if I underline text and then scroll down, does the underline scroll down with the text? What if I dragged the window to the left or right? I only watched the YouTube video and there was no scrolling (or dragging) while a drawing was visible in the demo, so guessing no?

Not OP, but I bought the $3 app. When annotating is active, you're drawing on the screen and other content is not interactive. When you deactivate annotation, the annotations vanish and other content is now interactive.

I'm guessing the app creates a transparent NSWindow the size of the screen, and you are drawing to that. That's why scrolling doesn't work.

In order for scrolling to work you'd have to do something like create a transparent window over the app you are drawing on, and scroll the application window that is below using the Accessibility API.

That's correct. I could have used Accessibility API to allow scrolling but apple would not allow me to publish my app on the app store as the app wouldn't be sandboxed.

Great idea!

One suggestion: don’t use Twitter as your support/contact system. I don’t have an account with them, don’t want an account with them, and so it’s a turnoff to think I might not have a good way of providing feedback or get support if I paid for this product.

Thanks for your feedback. Yes, I will change it in a couple of minutes as someone else also complained about it. However, the support link is at the bottom that takes you to a google form. You do not need a twitter account to get support for the product. I hope this helps.

The change is now deployed!

I agree with Zelphyr's statement and would add that Facebook should also be avoided for support for exactly the same reasons.

I would think the issue is not “avoid using X”, but “don’t _only_ use Twitter and/or Facebook”

As long as there’s responsive support via standard ‘open’ channels such as email or phone, why would you care whether others can use other channels (e.g. regular mail, fax, or home visits :-) ) to get support?

I find facebook the most friendly way to ask for support or interact with companies. Please keep it :)

Genuine question,

‘Friendly’ how? I’m wondering how it’s better than a ticketing system or email.

Who is using emails nowadays? Chatting via messenger is much more informal. Also most of my communications are via messenger, so it is nice to have one place for all.

i hate those chat bubbles that pop up. Unless its something that I need fixed asap I always email.

I like it, nice and simple. I tried it with Astropad so I can markup from an iPad and that works pretty well.

couple of things:

when screen annotation off, two finger scrolling gestures don't work (though scrolling with arrow keys for example still does). Not sure if that was intentional

It would be nicer if the erase tool was a real eraser, and not just a way to clear the full screen (since turning off annotations already does that anyway

I will add the eraser later but I am going to add undo/redo feature in the next release so that may be helpful to you in the meanwhile.

And, thanks for the compliment.

Also because you asked for feedback, and I'd like to understand how.

- When I draw, I can't scroll anymore.

- When I draw, I can't quit. The button to open the menu doesn't work and I see no button to exit.

I ended up with CMD + Q to close the application. I now see there's shortcuts in the menu, but I wouldn't rely on shortcuts for operations. In my opinion, shortcuts are shortcuts for buttons, not a substitute.

> When I draw, I can't scroll anymore.

This solves one major technical problem: how to make the annotations move with content

> The button to open the menu doesn't work and I see no button to exit.

Do you mean the button on the menu bar doesn't work? Definitely sounds like a bug; works well for me on the macOS 10.15.4. Also, the keyboard shortcuts work for me to toggle annotation.

> ... shortcuts are shortcuts for buttons, not a substitute.

Disagree. Shortcuts are for functions of the app, like menu items. There are many menu items in many apps that don't have buttons, but they have shortcuts. I would agree that there shouldn't be shortcuts for 'hidden' functionality.

Hello, sorry for the late reply. Yes, when you draw you cannot operate on other applications. Apple restricts it. There is a workaround for this but if I go with that then the app won't be sandboxed(meaning it can't be published to the app store anymore).

The button on the menu bar should work as only the visible screen is where the annotation takes place. If in case it doesn't work for some reason, you can always use the keyboard shortcut control+option+A to toggle annotate feature.

Hope this helps!

Nice work! I bought it and tried it with Sidecar and an iPad Pro. It works pretty well. Some feedback:

1. Make the color/clear buttons a little larger. The hit targets are very small at the moment when using a Pencil on iPad. It's easy to draw on the buttons by mistake when you mean to press them.

2. Add a “stop annotating screen” button to the buttons, separated by some space so it's harder to press accidentally. That way I can end the annotation session from the iPad instead of having to use the keyboard or mouse.

3. Add a “undo stroke” command and shortcut. Users of AstroPad should then be able to map this to a two-finger tap, which would give a really nice undo workflow for drawing on screen. https://astropad.com/magic-gestures/. When annotating it's pretty common to want to undo a bad mark without having to clear everything you've drawn so far.

Thanks for the feedback.

I will be implementing the 2nd and 3rd in the next release. 1st one I can do after. I can increase the size of the pen color selectors.

Since you're asking for feedback: how about a non-App Store version?

Yes, it is doable. Not sure if Apple has some policies restricting that. If not, then it is definitely doable.

May I ask why would one need a non-app store version? I thought users would trust the App Store more than other websites like gumroad, paddle, etc.

I’m sure everyone has their own reasons, but my personal idiosyncratic one I don’t like buying apps that require online activation—I feel as though they aren’t really mine. App Store apps moved to a new computer won’t run until you connect to Apple’s servers, and consequently, you would be unable to reinstall them in a theoretical future where Apple’s servers have gone offline.

Mind you, Paddle has this problem too, but some other systems, like FastSpring, do not.

Although as an additional addendum to that—and this is probably not going to make you want to use Paddle—there is a generic keygen that works for all Paddle apps, so I don’t mind buying them because I know I have a failsafe.

I don't think it's something that I'll need often, but I've bought it anyways, might come useful sometimes. Works good, doesn't take much memory, I like it very much and the price is very fair.

Out of curiosity what is Compzets.com that's linked from the app, is it the author's company or it's just an ad?

Thank you for your support. Means a lot to me. Compzets.com is the website that I developed when I was back in college. Since then I have been launching all apps, plugins, extensions, etc. under this brand. So, to recapitulate, it is not an ad :)

I’ll share it with my friends and advisors who are doing a lot of remote teaching at the moment. Unfortunately, I don’t think many of them would pay for software :/ It looks like a great app though, I might check it out!

This is what people are conditioned to nowadays, 3 dollars is too much for something that is actually beneficial.

I have 3 promo codes that I can share here. You can use one on the Mac App Store and install the app for free. I hope that it helps. All the best!

Promo codes:


Codes are all used, but thank you for providing them (and developing the app)!

That’s really depressing: Doing remote teaching but being to cheap to buy the person providing a tool a beer.

This looks really nice, congratulations!

Slack has something similar during video calls where anyone can draw on the screen and the annotation automatically fades after a few seconds. Might be a good addition to your product.

This app also has the feature to automatically erase your drawings on the screen. Check Preferences. However, it doesn't have the fade animation. Will add it soon.

And, thanks a lot for the compliment :)

Neat. In the demo are you using a stylus? Or are you using the trackpad or mouse?

Btw, Macbook's touchpad can be used with a stylus intended for a phone. (And probably other modern touchpads can too.) Specifically, you can conceivably write or draw if you enable double-tap-and-drag for dragging.

Apple's Preview app allows drawing with the touchpad without double-tapping, to sign on a PDF. Presumably someone could make an app that would switch to such a mode system-wide on a hotkey, and dialed down the sensitivity.

In the demo, I used the trackpad on my Macbook Pro. However, if you want to write, I think you may need a stylus.

Is it available on Homebrew? A lot of us avoid the App Store...

I am not sure how the payment thing would work on homebrew. I will have to look at this.

This looks great and will come in very useful when presenting visual concepts (keep the audience focused).

One suggestion for future improvement would be auto shape snapping. I assume most will use this with a mouse which can result in squiggly, unsightly lines. A number of iOS note taking apps detect a similar shape and snap to straight lines or perfect circles. Hope that helps and thanks for the app.

Thanks for your valuable points. I am currently developing these features and would likely come in the next update. You could easily draw straight lines, arrows, circles, and rectangles.

Just bought it and it looks great! One feature that Slack's video call has that would be nice to add is to have the possibility to auto-fade what you've drawn. Lets say if you haven't drawn something within 5 sec, what you've drawn slowly fades away.

Thanks for supporting it. The auto-erase/disappear feature is already there. You can set it in the Preferences. However, I will add the fade animation to it soon.

Ahh my bad! Great work!

Great app, I just bought it and I will try it on the next WebEx conference calls :).

Some remarks:

- the "Highlight cursor at app launch" has a "Start sdf sdfsdf" tooltip

- I can not change the keyboard shortcuts (when I click on the button to configure them, nothing happens)

- the default keyboard shortcut "Control + Option + A" presented in the menu does not work on French keyboards and requires instead to push "Control + Option + Q", which looks like a AZERTY / QWERTY configuration issue?

> - I can not change the keyboard shortcuts (when I click on the button to configure them, nothing happens)

It seems this is currently not possible. Would also be important to me.

Yes, that's correct. Custom shortcuts isn't implemented yet. I will enable it after I add the different drawing shapes. Thanks for bringing this up. This helps me in prioritizing features.

Congrats on the launch!

Its hard for us with a very mixed tech stack to realise something like this. I've started thinking about using VNC to share Autodesk Sketchbook from my Surface Pro to do presentations and splicing it together with my webcam using OBS for meetings.

If anyone has done something similar I'd love to hear it, main workstation is linux.

Used to use something like this all the time in compiz fusion with a graphics tablet, before spinning the 3D desktop around with a key combination and firing up some completely different workload on the rear face of the cube. Ahh, those were the days. Seriously though, if you like writing on the screen and haven't got a graphics tablet yet, get one. It's like a revelation if you do most of anything that is mouse intensive, and your future arthritic hands will thank you for it.

Also check out https://github.com/bk138/gromit-mpx

Wish you had posted this yesterday! I could have used it this morning. I bought a copy so I could use it for a presentation on Friday. Thank you for making it!

Suggestion: Make the diameter of the cursor highlight an option I can tweak.

Thanks a lot!

Point noted.

Can I ask you a question regarding the "auto starts on login" feature? I have been working on that feature on an app I have but my app simply doesn't want to start on login. I don't even know how to troubleshoot it as nothing gets logged to the system.log using the console app. I used this tutorial but not sure why it won't work:


Did you face any issues too? Any thing I can use to troubleshoot?

I used this tutorial and it worked for me https://medium.com/@hoishing/adding-login-items-for-macos-7d... but I had to do a small change which I have commented on this article.

Or you can simply use this https://github.com/sindresorhus/LaunchAtLogin

Are you registering your login item helper application with Launch Services?

Could you please elaborate on that? How would I do that?

Right now I am using `SMLoginItemSetEnabled` to set my helper app and returns `true` as the returned status. The helper even seems to launch my main app just fine if I run the helper alone. But it doesn't work after login :(

I did try running `lsregister -dump` but it returns a massive database and I have no idea how to even filter it for my app only.

Can you try lsregister -f on your app and its helper and see if that helps?

Nice app, just bought it. One feature request - when using touchpad there should be some key to activate annotation/drawing. It's hard to draw on touchpad while pressing it.

This would be a very useful feature. Will look into it. I have seen this in document signing apps. So, I think it should be doable.

This is really nice, buying it right now. Would like for an option to take a screenshot from this app itself, as opposed to Mac OS X's native screenshot taker.

i.e. if I have a power point presentation open up that I'm "drawing" on top of, would like an option to screenshot/record my screen, so I can save whatever annotations I have made.

Also would like to be able to add text boxes and type (as an addition).

May I ask what's the harm with Mac's native screenshot taker? Even if I include it in Presentify, you would have to press a hotkey to capture so, from a user experience point of view I do not see a difference.

As someone leading remote colleagues on UI/UX work, this was an instant buy for me. Congratulations!

thank you! Hope you enjoy using it :)

+ 10.12+ + AppKit

Suggestions: - screenshots are too small and on 10.14 video preview is missing - touchbar support - as someone suggested, if you demo sidecar + pencil you will get featured if your app is translated to 5-6 languages

I find myself wanting this every morning. How long ago did you start the app? It seems like the perfect time to launch it being that everyone is home.

I just bought it and will be using it tomorrow AM. Works great.

Not only is this great software, but the fact that it did not ask for overreaching permissions and did not try to connect to 5 different websites on the first run made it an instant win for me.

Thanks a lot for the feedback. It won't now and it never will in the future because I too hate that :)

Hee hee...so I can draw devil horns and moustaches on my co-workers in boring meetings? Excellent!

"helps you give better presentations by letting you annotate any screen, highlight your cursor, and more"


Haha, I did that once while I was testing the app and our video conferencing app froze for a couple of mins :)

Nice presentation website. I've also just tried your app. I think it needs an exit button. It's not obvious how to exit it (unless you know the shortcut) once you activate it.

hey, thank you so much.

The exit button is on the menu bar icon itself. One does not need to remember key shortcuts to exit. You can simply tap on the menu bar icon and then click "Stop Annotating Screen". Hope it helps.

I have auto-hiding menu bar turn on, thus I cannot click on it once Presentify is activated. I was thinking of an exit button next to the eraser/color picker.

Also check out https://screen.so/. It's free and works great. Was posted on HN a while ago.

This looks great, congrats.

Would love to see this on the iPad as well, know of a few corporate users looking for it. Happy to chat offline.

Thanks for the comment. Sure, I would be more than happy to chat. You can get in touch with me via the chat widget on the website https://presentify.compzets.com/

Looking forward to it.

How does this fare with the Apple Pencil via Sidecar? Would definitely try this out if it works well.

Works well with Sidecar when mirroring on iPad Pro.

The only thing I found is that the hit targets for the pen colors and clear screen button are perhaps a little small to tap with a pencil; I ended up drawing on the buttons accidentally a few times.

Switching colors with the keyboard shortcuts (1/2/3) and clearing with the c key works fine alongside the pencil, though.

I also instinctively tried to tap two fingers on the iPad as an “undo stroke” command, as that's how other iPad drawing apps often work, but that obviously does nothing in this case at the moment.

It would be useful to have an “undo stroke” shortcut in the app so users could map to the shortcut from a gesture (not sure Sidebar supports that but I think AstroPad does: https://astropad.com/magic-gestures/ ).

This is a great idea. I was wondering how could teachers draw on their iPad and show it on their laptop.

I just gave it a try on my iPad 7th gen and my MacBook (running macOS Catalina) and it worked great.

One thing to keep in mind though, when I connected my iPad to my mac via sidecar, many of the menu bar apps got hidden due to lack of space on my menu bar. So, I had to start the "Annotate Screen" via keyboard shortcut.

I will update the description on the app store that this works. Thanks again!

I've been looking for something like this for months! It's so painful using Zoom annotation tools with a mouse

I imagine it would work w/ Astropad if you aren't on Catalina for Sidecar

edit: I tried it w/ Astropad.... works great

Awesome work! Well worth the price for a nice, simple utility I feel like I will use everyday.

Thanks a million :)

Any comparison notes with the similar app "DemoPro - Screen Annotation"?

Sorry, I haven't used the app and can't find much from the limited screenshots on the app store. But from whatever is available I see it has a timer and Presentify has a cursor highlighter instead.

The different shapes are coming in the next release to Presentify so I am not considering it for the comparison now.

What did you write it in, out of curiosity? Obj-C and Carbon?

I wrote it in Swift 5.1 and used Carbon APIs for some features.

How's the Carbon work, considering your app is 64-bit?

Parts of Carbon are still around. It’s only the GUI parts that never made the transition to 64-bit.

(Source: my app uses a couple Carbon APIs, where I couldn’t get the newer Cocoa APIs to work reliably.)

Does anyone know an app like that for linux?

Thanks for this, well worth $3.61 CDN.

You're welcome :) Hope you enjoy using it!

feature request: ability to write text on the screen

Feedback noted!

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