I don't know about Strava, but I have a Garmin running watch. It's got a battery that lasts for over a week and stores all activities until it can be uploaded via phone. The only failure point there might be user error, but given we're talking about a 1 mile run, I barely count that as penance if I have to redo it.
The battery life of Garmin watches is astonishing. When I get a low battery alert, I still have several days to plug it in. If my phone dies, my watch stores my run until I get home, at which point it logs into my Wi-Fi network and uploads it automatically.
I had a bunch of Fitbits over the course of a decade and wish I'd made the change earlier.
