Speedometer is simple to use application with a speech option if you can not look at the screen, showing your current speed, max speed in km and mile, altitude, g-force and even little compass. Including GPS power signal indicator. Speed units: miles/hourkm/hourmeters/sec.g-force. The speed calculated by GPS so you need to be in a open space for a good signal reception from GPS Satellites. If the signal is low the accuracy is low, in this case the speedometer can show speed when is no real movement. You can switch to on or off speech option depend on your needs, if you want change speech language you need to change your phone language in the setting option (not all languages supported by speech engine) Default language is English. NOTE: not all devices supporting compass and accelerometer (g-force) sensors, if your device is not supporting you will not see them. If you have a trouble or bugs or idea to make efficient our App please contact us!