There are many use cases.
1. When walking in New York City, London, Paris, etc. you can be notified of restaurants that are empty vs. full, directions to the nearest subway station and time of the next trains to your route.
2. When walking in Disney World, Universal, etc. you can be notified of wait times to rides around you, times for the next parade or show, and directions to get to the attraction you want.
3. When walking, hiking or biking trails you can be given directions or notifications like 'route ends in 10 minutes' without checking your phone or watch.
4. Your glasses could notice friends or contacts you're walking by - or are near. And notify you - 'Your friend Jennifer is checking you out across the street'
5. Your glasses could watch out for and alert you to creepy people around you who AI thinks might rob or attack you. If this becomes a well made commercial, these could sell like hot cakes.