Draw2Measure Protractor App (for iOS devices) (Free app)

This app gives all students an alternative way to measure angles. It works with devices running iOS 8 or later. Students can place an angle over the screen of a phone or tablet, and trace along the sides of the angle with a fingertip or stylus. The app records the locations of the sides and then calculates the angle. For objects that may not fit on a screen, students can find measurements by rotating the device itself, which utilizes the built-in gyroscope sensor to measure the angle.

Available for FREE from the App Store