Digital Level is also known as spirit level, bubble level, surface level meter, waterpas, electronic level, laser level, nivel, plumb bob, level tool, clinometer, leveler, protractor, inclinometer, carpenter's level. A digital level, bubble level or simply a leveler is an instrument designed to indicate whether a surface is horizontal (level) or vertical (plumb). This level tool is handy, accurate, simple to use and incredibly useful in scenario where you don't have to carry a level meter with you all the time.

A traditional modern level meter has a slightly curved glass tube which is incompletely filled with a liquid, usually a colored spirit or alcohol, leaving a bubble in the tube. At slight inclinations the bubble travels away from the center position, which is usually marked. Bubble Level, Spirit Level or Digital Level app tries to mimic the real level meter and displays the data as real leveler would.