The GPS have a real time clock inside it - so you could compare with the time for that. Turning it on for literally just 1 second (to get the time off it) and then turning it off once an hour won't hurt battery life noticeably - it wouldn't be getting new time from satellites, just telling you what time was in the GPS RTC.
It'd be worth doing some comparisons but because GPS is so time critical, the GPS chip might have a better (temperature corrected) RTC.
Another thing you might be able to do is perform your own temperature compensations - so put the Bangle somewhere warm with constant temperature and measure how fast it runs, then put it in a fridge and do the same, and I guess you might be able to use that to do some manual compensation. I have no idea how good it'd be though.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
The GPS have a real time clock inside it - so you could compare with the time for that. Turning it on for literally just 1 second (to get the time off it) and then turning it off once an hour won't hurt battery life noticeably - it wouldn't be getting new time from satellites, just telling you what time was in the GPS RTC.
It'd be worth doing some comparisons but because GPS is so time critical, the GPS chip might have a better (temperature corrected) RTC.
Another thing you might be able to do is perform your own temperature compensations - so put the Bangle somewhere warm with constant temperature and measure how fast it runs, then put it in a fridge and do the same, and I guess you might be able to use that to do some manual compensation. I have no idea how good it'd be though.