I'm recently enjoying walkscape, which is an RPG where you have to walk in real life to progress in game activities, such as crafting or fighting.

It's in closed beta, but you can sign up for the next wave of beta invites and I got in pretty fast

Also, I downloaded streetcomplete but haven't really gotten around to it. It's an app where you map out your surroundings for open source maps with Infos, like opening times at a bank or the width of the street or the type of road, etc. A cool concept, but I always forget about it