How I built a location-based app without storing any GPS coordinates

Privacy was the #1 rule when building neighOWL. Since it's a hyperlocal forum, I needed location, but I refused to store it.

solution: The browser captures the GPS, rounds it heavily (blurring it to about a 1km zone), generates a zone hash, and only sends the hash to the database. The exact coordinates never leave your device. Even as the creator, I can't see where you are.

Anyone else building privacy-first tools? What trade-offs did you have to make?