thank you for your hard work!
I bought your app in the Play Store last October. I installed it on a low-cost 4.4 android tablet and it was working very well connected to my OnePlus 3.
However after the last update, it isn't anymore available for my tablet. In a previous post you said that there was a problem related the gps.
I look for the manifest and I found this line:
I didn't have time to check your code on github, but this line in the github repo is not present. However I don't think the gps is strictly required, at least for OTG mode, so you could use:
<uses-feature android:name="android.hardware.location.gps" android:required="false" />
and then eventually disable the functions that require a gps.
My 2 cents