API doesnt work when apk downloaded from play store

I have an ionic app that works fine when installed locally (a release build apk, signed and zipaligned, etc). When I upload that same apk to the play store and then install it on my device, the API no longer works… I can’t log in etc. I cannot debug it, of course, so I cant figure out whats wrong… Is this some kind of whitelist issue (which is installed)?

Help?