Apple

I find a lot of value in “Siri set an 90 minute ‘laundry’ timer” etc. As small of a thing as that it, not having to pull out my phone ever time I set a timer (and I set many through my day for various things) is awesome.

Given you work in PT, it might be useful to, for example, have a 60 minute timer for a given session with a client. Or a 5 minute jump rope timer. Etc etc.

If you like to record your own fitness that’s probably the single most useful thing a watch is good for as well.