I got this message from Google Play about this:
I was unable to tell if the ArcGIS Android Runtime 100.4 is ready for 64 bit.
If it's not, apps with the ArcGIS Android Runtime will be kicked out of Google Playstore on August 1, 2019.
Given the length of development cycles in the SDK, I hope I have mentioned this in time.
I'm guessing these apps will depend on it also.