I first learned of Street-Complete here and I really like it.
It’s satisfying to walk around, complete little tasks, and get prizes, scratching a similar itch to Pokemon Go.
Stuck waiting for someone? Add opening hours for a few local businesses.
Have a long walk ahead of you? See if you can add/check house addresses as fast as you can walk.
Want to walk off a few beers before heading home? Complete some tasks in the bar street.
Its a very constructive way to “be right” on the internet.
You can also add “little” objects like benches, recycling containers or trees in your near environment to the map that come with their own sets of questions