Speed Gun is an app that lets you calculate the speed of any moving object with your Android's camera.
Speed Gun is very easy to use. All you have to do is enter the shortest distance between you and the object, point your camera in its direction, and follow the movement with your finger on the screen. This way, you can see how fast the object's moving in real time.
It's important to note, Speed Gun can only measure the speed of objects moving horizontally, i.e. from one side of the screen to the other. If the object is moving towards you, the speed calculation will be incorrect.
Speed Gun is an interesting app for calculating the speed of moving objects. It has plenty of uses, like training for various sports, for example.
