https://apps.garmin.com/en-GB/apps/ea97fdfa-0339-464e-a665-d4dfcbc9a4d2 (as widget)
https://apps.garmin.com/en-US/apps/6761e7b5-db5d-47a2-baef-a3a42e3d7f94 (as app)
I wanted a quick way to check my heart rate without starting an activity, so here it is. I also wanted to see how close I could get it to having it look "native" (at least on the fenix 3, I don't think the other watches have chart widgets like this natively).
Changelog:
1.3.2 - Fix stupid bug in range display
1.3.1 - Longer periods, notify on HRM connect
1.3 - Configurable period and colour, autoscale y axis, port to app
1.2 - Persist data across sessions, compatibility with square watches, visual tweaks
1.1 - Chart that looks like Garmin's
1.0 - Initial version, just numbers, never released