Habpanel Language settings


I am loving Habpanel and use it a lot.
Especially after big performance improvments by habpanel-filter.

However I have one issue I cannot solve.
I have created a family calendar with upcoming events.
This shows perfectly 24hrs and weekdays in German on my German Windows 10 PC (Chrome).
The same applies to my German ipad.

My android tablet though (set to German as well) shows AM/PM as well as english weekdays.
This is true for the default browser and HabpanelViewer.

I am not experienced with Android and checked all settings on the tablet.
Any suggestions?