Coming over from OTD in GA. I am creating an app that will use a smartphone to determine boresight. It will work on a scoped rifle, tactical optics and hunting/sniping scopes. It allows the user to do three things, bore scope in reference to the rifle chamber and store chamber location, record the sight setting after the rifle is zeroed and recall the sight setting and verify the setting using the rifle chamber. This means that you can check the zero any time you want or suspect that the sight setting has been disturbed.