I there a way I can set up my app so that things like the database and images can be optionally downloaded/updated when when I make changes to the data, without updating the app. i.e. a kind of syncing with the new data?
I would have the database and images on my server and the user can update or not without having an icon on their phone saying there are updates available.
As far as I know, Android databases are just sqlite.db files. You should be able to have a button in your app that downloads a new sqlite.db file from your server. Have it replace the file that is already on the device and you should be good to go!