I would like to increase the internal storage by linking to the external SD- card. I am just installing navitel (Android) which consumes 1.2GB of internal storage. I created as root a link 'NavitelContent' from the Android storage '/data/sdcard/' to the external vFAT SD -card '/run/user/10000/media/sdcard/NavitelContent' and installed navitel. However, when running navitel I tells me that some files were not installed. I assume that there is a problem with the permissions. Any idea what could be wrong and how to fix it?

Remark regarding offline navigation: I'll try navitel, although it cost me 13 Euro. navfree has terrible routing and I do not get any audio from OSMAND (I tried all settings). I tried to sideload Sygic, but it seems to rely on the Google framework, which I try to avoid.

When trying to access media files that were on my SD-card, I noticed that Android programs didn't seem to understand symbolic links. Or atleast the file browser on the programs didn't show the symbolic linked folder.
So maybe that is the problem for you aswell?