I'd like to find a wearable that can help track my sleep and heart rate. I'm definitely not interested in device that requires a subscription to use, or to collect/present some or all of my health data to me.
I looked into Withings' devices and they look more or less like what I'm looking for - I'm going to try a Pulse HR but beyond that, I'd like some other suggestions.
Watch functionality is optional, but if it's not a watch it needs to be as small/un-intrusive as possible because I do also wear a watch.