I have an app on the Mac and a Prop device that connects via USB. I want to prevent someone reverse engineering and adapting their own device to avoid buying it but don't want to get into adding licensing to the app. On launching the app it connects to the Prop via the silabs cp2110. It would be easy to send some pseudo random info like time date, mouse position, pixel color under the mouse etc to the Prop for it to do some math and reply with some response based on a formula. I am looking for ideas on how this might be done. Any thoughts?