How do I update?

I want to build a mobile game and i want to upload on store. But in the future I want to make some updates . How i make my game to autoupdate? If you understand.... for example the user has already downloaded the game on the device

I believe this to be cell configuration of the player and not your game. Who identifies if the game has an update is to own google play. The game or other application will be updated only if the user allows.