Show HN: Free tool to mark points and polygon regions

A new free browser tool called tack. has arrived with a very simple promise: drop an image in, click on spots or trace shapes, and get neat coordinate data out the other side. It’s aimed at anyone trying to turn a picture into something usable — from game makers to people mapping rooms, floor plans, and clickable areas. The big selling point? Your image never leaves your device, which gave the whole thing an instant “finally, someone gets it” vibe.

But the real action was in the comments, where the community immediately split into three classic internet camps: the impressed, the inspired, and the mildly offended. One commenter was genuinely delighted, calling it “super cool,” then casually stole the spotlight with a wonderfully specific life story about asking an AI assistant to help plan a zig-zag string-light layout for a balcony. Honestly, that may be the most relatable “accidentally inventing a use case” moment in the thread. Another commenter kept it short and sweet with a simple “great stuff,” the digital equivalent of a nod of approval.

Then came the drama. One mobile user spotted the line saying the app works best on a bigger screen and fired back with peak sarcastic energy, basically asking: if you know I’m on a phone and the app won’t work, where’s my nice little demo video instead of disappointment? It’s not a full-blown scandal, but it’s exactly the kind of practical complaint that turns a quiet launch into a tiny comment-section soap opera.