A service provider may provide a companion container instance associated with a mobile device in order to facilitate operation of the mobile device. The companion container instance and the mobile device may be associated in a database operated by the service provider. Furthermore, the companion container instance may execute various operations on behalf of the mobile diver based at least in part on a task definition indicating a software function to be executed by the companion container instance. The software function configured to execute the various operations on behalf of the mobile device.