Know which stalls are occupied
Have you ever been to a large shopping mall with indicators showing which parking spots are available or not? Well, imagine having that but in public restrooms. All over the country, there are screens in bathrooms displaying which stalls are in use and which are available. No more awkward peeking below the stall door to see whether a closed stall is occupied or not.
This is a handy system we wish was available across the entire world. There are already so many problems with using a public bathroom (hygiene and whatnot), and the last thing anyone needs is having your feet eyed by a complete stranger.