Tracking player movement in a mobile app

I’m working on an android game (and iOS eventually) where I’d like to be able to tell when a person is moving in the real world.

I would be fine with either creating my own logic using something like geolocation, although ideally I’d love to simply have an API like Google Fit where I can sync up the player’s steps (so that it could keep track even when my game is up).

Unfortunately after working my way through the Google Play Services configurations, I’ve discovered that it’s a bit limited at the moment in terms of blueprint usage (Signin, Leaderboards, IAP, and Achievements).

I have no clue what the process would require to integrate a non standard Google Play Services service(Fit), so I’d appreciate any advice along those lines. Or any other alternative where I’d be able to tell if a player is moving in real time.

Thanks!