Android Studio - Google map still blank on real Android device on release apk

Make sure you enter your release API key in the google_maps_api.xml under the release folder.

First, switch to Project view by using the dropdown in the upper left of the Project Explorer. Then, expand app/src/, and you will see subfolders debug and release. Under there, you should see two separate google_maps_api.xml files under debug/res/values and release/res/values.

Make sure that the release API key is in the google_maps_api.xml file under the release/res/values folder, since this is the one that will be used for the signed release apk.

i was tired of trying over and over again, it turns out that PlayStore has something called App signing certificate, and the map works after i copy that sha1 and paste it in the google console for the android map.