Pro Ballistic Chronograph on your Android device. The best way of measuring an air guns power output without a an actual chronoscope. Please make sure you try the Lite version for free before going Pro. Chrono Connect Mobile Pro will monitor the speed of pellets leaving your air gun, rifle, pistol and display the speed and power for you in your chosen speed and power units, in a list of shots, and even in a graph. Pro version includes many advanced features including. Unlimited shots in one go ( no 3 shot 'Lite' limit ). Full list of shots in the string. Graph of shots in the string. Full shot and string management.comprehensive pellet database ( no need to manually enter weights and BC values for most pellets ) - Comprehensive rifle and pistol database. Visual over power warnings. Chrono Connect Mobile works by reading your gun firing a pellet over a known distance so all distances should be entered as accurately as possible to ensure accurate readings. When set up and used properly, Chrono Connect Mobile can be within a few feet per second of a real chronoscope device. This app was created because I have heard of people doing the following things to determine the power of their airguns when they don't have a chronograph. Shoot into a yellow pages and count how many pages were shot through. Shoot at the ground and measure the 'mushroom' of the pellet. Shoot a coffee can. Did it go through 1 or 2 sides? - Shoot a soda can in various places, if it goes through X place its X power. Chrono Connect Mobile is a far better way than any of these methods of determining the speed and power of your gun. As there are variables that are beyond our control you should not rely on Chrono Connect Mobile as your sole method of recording speed and power and should test the power of your gun using a real chronoscope if in any doubt.