Bubble Level Meter 3D, also known as Best Level, is a free application developed by Smart Level Tech Apps for Android devices. This application is designed to measure whether a surface is horizontal (level) or vertical (plumb) using the accelerometer of the device. It is a precision and reliable tool that shows the level of the surface in 3D. The app has been tested on many devices and works the same as its physical equivalent.

This application is useful for carpenters, bricklayers, stonemasons, building trades’ workers, surveyors, metalworkers, or anyone who needs to check if a specific surface is flat or dumb. The Best Level application can be used to measure the elevation, roof, table, shelf, or any inclination in construction. The app contains a calibration option and the bull's eye level (also known as circular bubble) that measures the level simultaneously in two dimensions – horizontal and vertical. If the measured surface is flat, the ball shown on the screen will be at the center, and if it is not in level, the ball will not be at the center and at a distance from the center as it's not in level.