About Protractor

Protractor is an iOS app from Appcellent. It uses your iPhone's built-in motion sensors and camera to measure angles, slopes, inclines, and level — so you can check a mitre cut, hang art straight, or read a roof pitch without a physical protractor, level, or inclinometer. It's free to try and ad-free.

Why we built it

Hardly anyone keeps a protractor and a spirit level in their pocket — but everyone carries a phone that already has the sensors to do both. We built a simple, offline app around them so the right measuring tool is always one tap away.