Need help using Obsidian with older Android Tablet

The latest version I got to work is 1.6.5.

I'm using a Likebook Ares (eInk, Android) with the Android System WebView Version 74.0.3729.186

I am sadly not able to update it, the tablet can't seem to work with newer versions.

What I noticed is that .apk 's installed just fine, but as soon as I had to install .apkm 's, it didn't work anymore. For 1.7.5, I tried changing architectures (both together/alone) and changing the DPI (320/all). Neither worked.

Thanks for your help!