Thanks for all your advice on my previous post.
I've now tried two older fitbit trackers; Inspire 1 and 2.
The 2 measures heart rate and graphically shows bpm (beats per minute) per day with the time spent, in pre defined 'exercise zones'; peak, cardio, fat burn. It only allows one custom zone.
As an older person with a heart problem, the zones are not applicable and only display in the app, for a day, not a week. The data for the custom zone is only shown in total, not graphically, as for the pre defined zones.
Ideally, I'd like a device/app that enables you to create 2/3 custom zones, graphically displays them and a summation for a week.
Any suggestions, Thanks