I am working on an app which I am testing as a closed alpha on Google Play however when I update the app to fix bugs or add features it requires the user to download the whole app file size again. Not only that but the file sizes seem to stack up, my app started at 24mb and after only 2 small updates its now passing 70mb!!!
When looking into this problem I read that Google uses delta updates to just replace the files that have changed but my app does not appear to be doing this.
Update: I spoke to Google dev support and they were useless, they said the question was "out of our scope" and that they were not trained for helping with development issues, however I see this issue as something that is out of my control but I hope i'm wrong because Google wont help.
Any help is appreciated.