Phone freezes then restarts itself

Happenin to me since a week.. It happens often when I tap 'send' in the SMS App.. But also in other random situations. Like swipe to Multitask and others. Right now it's in a loop since a hour. Gets to the Jolla logo and restarts again and again......

Remove the battery. It may help to recover a 'normal' behavior. I'm experiencing something similar. The phone is shutting down or restarting while I'm writing a SMS and even when I'm doing nothing. When it shuts down, I restart it, it says battery level 4% and it stops immediately. I let the phone for one hour level without recharging it and I restart it one more time. Everything is normal with a battery level at 54%. My feeling is that there is something wrong in battery power management and when the calculated level is below a threshold the phone stops immediately. But that's just a feeling. I'm running 1.0.5.19. I'm a little bit tired of all these issues.

I have the same problem. Battery goes from 70% to something like 4% and the phone shuts down. I have the feeling it is getting worse, the phone restarts severals times a day.

By me no android but rarely (it seems to be related to incoming sms) all apps are killed.

All of the above seems to point to the same pattern: a sudden drop in the battery level. It is interesting that in so many cases this is provoked by sending an SMS. It makes sense since sending an SMS results in a spike in the current drawn from the battery which inevitably results in the voltage drop. Receiving an SMS or making/receiving a call would have the same effect. All of these actions involve the cellular radio which increases the current by an order of magnitude, if not more.

My immediate suggestion would be to clean the battery contacts. Cotton buds or just a piece of cotton wool wrapped around the end of a matchstick and dipped in propyl alcohol (the stuff used to clean magnetic heads or CD lenses) and a good scrub should do the trick. If that does not help then try a new battery.