Redlegs!!! Zero-Verify is the name of the app with sensors that I have been working on since 2010. Remember should hit and did hit. The app will boresight(should hit) and when you save your zero(did hit) will store your zero for when you need to verify based on total deviation from your rifle chamber. Need your comments, guidance, and push across the valley of death for entrepreneurs. I need a sounding board the app and sensors will retail for $185 and store data for as many rifles as you want, it is universal in nature. It's all high school math except for the sensors and the app they are rocket science. Become a part of my advisory board.