Bubble

Over 6 million downloads! A Bubble level. Hold any of the phone's four sides against an object to test it for plumb/level, or lay it down on a flat surface for a 360° level. Features: Calibrate each side of the phone independently. Show the numeric angle. Speak the angle out loud. Flash the light, beep, or buzz when level. Show the angle as pitch. Tap screen to lock angle.