After installing the web extension and clicking its icon it shows a QR code that is scanned by a phone which opens the web app in the browser. When the WebRTC connection has been set up between the devices you can steer a dot on the computer web page by holding a button and pointing the phone. The app also has other presentation clicker features like switching slides, drawing, presenter notes, and can also be used for remote controlling some videos (tested on YouTube and Plex).

Firefox extension: https://addons.mozilla.org/sv-SE/firefox/addon/clikr/ Chrome extension: https://chromewebstore.google.com/detail/clikr/oalndbmcbpchb... Home page: https://www.clikr.app/

I've always been fascinated in how much the web can do. This project started as a fun small POC many years ago when some of these native app-like functions were less common. I got the idea to see if I could make my phone control a "laser dot" on my computer just by tilting the phone like a real laser pointer. Being a web guy I went with web extension + web app. Surprisingly I think I got the basics working in an afternoon or two, having some experience with web extensions from before. Getting the user experience smooth and stable and adding other presentation features in various online tools took more time...

It uses RTCPeerConnection for the communication, Metered as signaling server, and a small protocol for the commands (point, switch slides, etc.). The deviceorientation event is used for getting the orientation (which has to be explicitly allowed on some devices). One issue here is that the angle values don't actually mean anything without a reference. Therefore the first pair of angles received in the extension becomes the origin for that "pointing". The origin on the screen is the middle of the viewport and additional received angles move the dot with those origin values as reference. I.e. it will always start in the middle. This is of course not as good as a real laser pointer but I think it works quite well when you've tried it a bit. Distance to the screen and its size will matter for how much to move the dot which is why there is also a calibration tool.

I like the other features too but I think the laser pointer is the fun one.

There are some paid features (one-time payment, no subscription) but the laser pointer, basic presentation features, and video remote are free and doesn't require an account.

It has some users but it's hard to get them to give feedback so honestly I don't yet know much about how it's performing in real situations. If anyone here tries it out please tell me what you think.

Show HN: Clikr – Virtual laser pointer that follows where you point your phone