Android, sideloading applications and keep them up to date via Google Play

Question

My company would like to give an Android device to a group of our selected customers.

Doing that, we would like to provide users with our mobile app. The app is already

Answer 1

As per January 2015, this appears to be impossible. Here is the response I got from Google Play Developer support:

Side-loaded apps do not update via the Play Store. If you would like the app to update, you will need to uninstall the app on your phone and reinstall the app via the Play Store.

I wonder if anyone found a way around this?