I have used a stop watch in the past to figure the speed of the pitch and it worked well. I found this in the app store today that lets you set all the different pitching distances 35/40/46/60.5 and lets you set a custom distance, I choose 43 feet naturally. It's called Baseball radar gun high heat by Handtechnics. I found it on my ios/apple so I'm not sure if it is available on android.