In a move similar to reddit or twitter, Strava is restricting API usage, and other policy changes.
I think an alternative to strava, which is also federated, would be really cool
EDIT: I know you can record teacks and keep them offline and there is plenty of ways to do so. I think the main aspect of Strava is the possibility of sharing the activities with contacts on strava itself. Like for peertube or pixelfed, the fediverse has the potential to allow any user to share what they like and the other users can see, boost, comment, from their mastodon, pleroma, froendica or wharever accounts. The fact that someone wants to share a track is his own business.
Not federated but a really good selfhosted open source project that’s coming along nicely: https://wanderer.to/
Seems only for hiking and there’s a whopping one single trail in all of Germany listed.
You upload your own gpx data from outings to your own hosted instance. its got a specific scope of features, I like it for what it is. Use it for mountain biking. Certainly not a strava alternative without other apps helping.