Hi, I am using OwnTracks on my Android device to log position into PhoneTrack-OC. For some reason, it sometimes gets a `NaN,NaN` position, which it sends to PhoneTrack-OC. Not sure if the implicit conversion is being done in the app itself or in PhoneTrack-OC, but this results in points at GPS coordinates exactly `0, 0`, which is obviously wrong. I think this is happening to me because I use LineageOS with microg on my Android phone. Then, the location provider is not Google Play Services but microg one, which can get a bit buggy and return `NaN` from times to times. This is actually quite hard to debug as, so far, I did not find any way to generate such positions on demand on my Android device. The workaround I have in mind at the moment would be to simply discard `0, 0` GPS coordinates points in PhoneTrack-OC. This seems fine for me as a real GPS data point will most likely never be at this exact position (first because this is quite improbable to get such a round position, and then because this is in the middle of the ocean). I think we may further restrict with the precision value, I should double-check this. What do you think? P.S.: I'll also open a bug on microg repo btw.