On device only, no play store, with GrapheneOS.
I am thinking about a Garmin watch and using it with Pulse. My cardio is really bad and it has been starting to cause all sorts of health issues, so I need something to track my heart rate while I go on walks to build my stamina back up so I can start actually working out.
https://repebble.com/ maybe? Or https://pine64.org/devices/pinetime/ ?
Personally I have a Fitbit, and it works on GrapheneOS, though I’m not sure if it would still work without Play services.