An inclinometer is an instrument used for measuring angles of slope (or tilt) elevation or depression of an object with respect to gravity's direction. Clinometers measure both inclines (positive slopes as seen by an observer looking upwards) and declines (negative slopes as seen by an observer looking downward) using two different metrics roll and pitch.

âš« Free
âš« Simple and Straightforward
âš« Can be used as Clinometer or Bubble Level
âš« Measure Slope using roll or pitch
âš« Use camera to measure inclination and elevation remotly
âš« Absolute or relative measurement

Roll

This is the rotation of the phone around the axis perpendicular to the device screen. Use it to measure inclination with any side of your phone or remotly when using the camera.

Pitch

This is the angle between a plane perpendicular to the device's screen and a plane parallel to the ground. Holding your phone screen perpendicular to the floor will give you a pitch close to zero. Use it to measure a surface slope when you phone is landing on that surface or an object elevation when using the camera.