ON Protractor is an Android app developed by PotatotreeSoft that transforms your smartphone into a useful protractor set for quick angle and slope measurement. This app is designed to help you measure the angle of everything conveniently and accurately with your phone anywhere, anytime. It is a versatile app that combines four different angle measuring modes in one app, which includes Touch Measure On Screen, Touch Measure with Camera, Plumb Measure On Screen, and Plumb Measure With Camera.

The app is very easy to use, and you can switch the protractor measurement unit between degree and radian by just a click. It is designed to cater to your needs in measuring the angle of different types of objects, from small objects to huge ones, and even objects far away such as buildings. With ON Protractor, you can now always bring an angle measuring pack with you as in your smart phone.