by Serg Glynianskyi.
I'm sorry.
You was right...
I checked... checked... checked... and finally found....
Once in ver. 1.9.7 I tested course for teacher in german... I forced this course to DE lang....
Now such option in this course was dropped to default, but, probably, it was fixed somewhere deep in the database ....
Now I forced RU to default in this course - and thank to God - Moodle mobile began to work fine for me!!!!
Thank you for help!!!!
We can close this topic!!!!
One more short question - how can I trace my server responces as you do it? How can I look for errors in ios app? Can I do it through logs, rest or api queries? or it is only your possibilities as developer og rhe Moodle Mobile ios app?