Notation Pad - Notation Pad is the Easiest way to write sheet music with notations on iOS/Android.
Angle Finder™ - Angle Finder™, now rebranded to Protractor+, is an app that offers a handy protractor tool on your phone.
Sibelius - Sibelius is a virtual score creation tool which allows composers to easily create new piano scores, developed by Avid.
Clinometer + bubble level - Clinometer+ bubble level is a handy tool that measures angles and inclinations using your device’s camera.
StaffPad - Write music naturally on your Windows Surface Tablet.
Pocket Ruler AR - Pocket Ruler AR is a pocket ruler app that lets you measure objects and distances with your phone.