Best approach to autoupdate Android App.

Hi guys!, im new in the community
We are currently developing an app for the TC51, we work with a large quantity of devices located in different places witch acces to WIFI,  we need to  keep this devices updated with the newest version of the app, something like launching a remote app update in all the devices

wich will be the best approach ? if the APK is located in a central repository?

PD:i read that the StageNow app , can do something like this , but all the devices need to be in the same network

Thx in advance

Cheers