After struggling some days with this problem I found a solution that works for me, maybe it is of help to others!
Environment: Samsung M30S (6000mAh battery!), Android 9 (latest uodate), OruxMmaps: 7.0.2 (current version).
As suggested I set "power mode" to "optimised" (power saving off) and turned off battery optimisation for OruxMaps application.
But this was not sufficient: As soon as phone changed to standby Oruxmaps tracking was suspended and only restarted after turning on the screen (with a stright line...)
To better understand the problem I tried another tracking application: "GPS Logger".
It has an option "Keep GPS on between fixes". With this app running (and option set to ON) also OruxMaps continues tracking! Even in standby mode.
It seems that Android location Services have to be kept alive somehow.
So I found another application: "GPS Locker". It does exactly what is required: keeps GPS alive.
Supported by this "assistant" OruxMaps works perfectly:
The quality of the track is superb: 2-5 meters accuracy on all points (independent of OruxMaps tracking parameters).
Battery drain is acceptable: 1 hour tracking takes about 3-4% of battery capacity (the lower in flight mode) so 20 hours of tracking should be possible.
Handling is a bit laborious:
You have to change power mode and start GPS Locker before starting Oruxmaps
Thanks for the wonderful OruxMaps application!
Good luck!
Update Feb, 21st:
MEA CULPA! Thanks for matt's advice!
I trusted Google Playstore that had updated my older version to 7.0.2!
Now I've installed 7.5.8 GP and tracking works in standby mode, without GPS Locker, perfect!
Environment: Samsung M30S (6000mAh battery!), Android 9 (latest uodate), OruxMmaps: 7.0.2 (current version).
As suggested I set "power mode" to "optimised" (power saving off) and turned off battery optimisation for OruxMaps application.
But this was not sufficient: As soon as phone changed to standby Oruxmaps tracking was suspended and only restarted after turning on the screen (with a stright line...)
To better understand the problem I tried another tracking application: "GPS Logger".
It has an option "Keep GPS on between fixes". With this app running (and option set to ON) also OruxMaps continues tracking! Even in standby mode.
It seems that Android location Services have to be kept alive somehow.
So I found another application: "GPS Locker". It does exactly what is required: keeps GPS alive.
Supported by this "assistant" OruxMaps works perfectly:
The quality of the track is superb: 2-5 meters accuracy on all points (independent of OruxMaps tracking parameters).
Battery drain is acceptable: 1 hour tracking takes about 3-4% of battery capacity (the lower in flight mode) so 20 hours of tracking should be possible.
Handling is a bit laborious:
You have to change power mode and start GPS Locker before starting Oruxmaps
Thanks for the wonderful OruxMaps application!
Good luck!
Update Feb, 21st:
MEA CULPA! Thanks for matt's advice!
I trusted Google Playstore that had updated my older version to 7.0.2!
Now I've installed 7.5.8 GP and tracking works in standby mode, without GPS Locker, perfect!