Some ideas: 1. Social Silo-busters: Couple the evils of the garden walled social network approach with posts on how hard is it to make friends later in life, add a pinch of all that useless time spent in the car commuting (scraping the bottom of Spotify or Audible) and you arrive at: ad hoc voice-based social networks based on proximity, e.g. through limited range (100m) FM transmitters (one cheap way would be to use…
The buzzer for restaurants, why can't it have a screen to display menu, or let your preorder? Burguerlich in Hamburg has screens embedded in the tables (which come up and down) from which you can order, seems close enough: https://www.tripadvisor.com/Restaurant_Review-g187331-d73509...
You could order before you even arrive at the restaurant. The restaurant can track and spam you in return. A company building the app for the restaurants can collect heaps of sellable data. Why hasn't anybody done that yet?