This app can be used as a primary instrument in flying planes as it provides information about the orientation of the aircraft with respect to the earth’s horizon. The indicator represents the actual position of the wings and nose of the plane with horizontal lines. The horizon bar at the center separates the sky and the earth. Along the edge of the dial there are degree indices marking the bank angle.

This App CAN REPLACE A part of a flight director display, is an instrument used in an aircraft to inform the pilot of the orientation of the aircraft relative to Earth's horizon. It indicates pitch (fore and aft tilt) and bank or roll (side to side tilt) and is a primary instrument for flight in instrument meteorological conditions. Attitude indicators also have significant application under visual flight rules (VFR), though most light aircraft are not required to have them installed for VFR operation.
The essential components of the indicator are:
• "miniature airplane", horizontal lines with a dot between them representing the actual wings and nose of the aircraft.
• the center horizon bar separating the two halves of the display, with the top half usually blue in color to represent sky and the bottom half usually dark to represent earth.
• degree indices marking the bank angle. They run along the edge of the dial. On a typical indicator, there is a zero angle of bank index, there may be 10 and 20 degree indices, with additional indices at 30, 60 and 90 degrees.