I was toying with the idea of using an open source fitness tracker.

Potentially allowing users to build one themselves, as a part of the whole DIY open source hardware ethos stuff.

Build a fitness tracker ring similar to building a seed signer.

And I want to give runners the options to store run data in nostr relays and blossom servers.

That way if someone comes out with a better running app on nostr, you can import your run data to the other app.