The Khmer Smart Compass or Trey Visay app is like a real compass. It can be used for navigation, location and direction. The Trey Visay app can detect metal around you. A high level of interference from metal represented by high magnetic strength in red color or in yellow color leads to inaccuracy of the compass. You need to calibrate your phone by rotating in 8 figure direction. The normal magnetic strength in dark green color is around 49 micro-Tesla (uT). You can use the Trey Visay compass