I've been looking into using my #smartwatch as a #dumbphone This is what I've learned so far – 1/9
Battery can definitely be an issue, which is why the Apple Watch Ultra seems to be the most popular choice with people who try this (after scouring countless Reddit threads).
However it really does depend on how you use it. I'm using an Apple Watch SE from 2021, and it easily lasts the entire day. Unless I'm actively streaming music while tracking a run, or using the gps for a long time.