Four things happen when you install Reva. Nineteen questions, one to a screen, about five minutes. A reading of what your answers add up to, quoting what you said, then three names for the pattern — you pick one. One pause, run for you, so you know what it looks like, with nothing blocked yet. Then you choose which apps get a pause; iOS handles the permission and Reva is never told which apps you picked.
Before the first real pause fires, Reva takes a whole screen to tell you that the pause will stop working, and that it will measure the day yours does.