While you are on the site, in your browser find and click "Add to Home Screen" A CGN beaver app icon will then be created to your phone that is directly link to the site.
Note: This feature may not be available in some browsers.
comp has longer receiver so the screwholes won't line up. Beretta makes a pic/weaver rail that fits a400/1301comp receivers. (but it raises your optic a bit more)
The Trijicon SRO has the same footprint as the RMR. The sight does not come with a mount, so depending on your application, you may need a specific mounting kit or adapter that you can purchase from Trijicon.