Track jumps to certain points an back

Keep hunting for settings in your Android device that might interfere with the QField positioning service. If you are getting smooth tracks with that last build which is de facto 4.2.2, it really boils it down to the OS interfering here.

If you can easily remove and re-install QField 4.2.2, that’d also be a good test.

I will do my best. Can you give any direction? I have no clue at this moment.

I was thinking, maybe the problem is caused by installing via Play store. So I deleted QField 4.2.2. and installed it through the apk from GitHub. However, this did not solve the issue.