Neither of the two methods I described require looking at the phone during the movie.
1. If you’re going to use the cues, you look at them before the movie starts.
2. If you’re going to use the timer, the phone will vibrate in your pocket. Granted, if you have a loud-vibrating phone, that could be disruptive (although not as bad as the screen being on or ringing, and not worse than a person getting up to go to the bathroom).
When the cue/timer happens, you leave the theater. While you’re peeing you can look at the app to find out what’s happening in the movie.
