Battery optimization based Android interview questions and answers

What is doze mode?

Device enters doze mode if, an user leaves it unplugged and stationary for a period of time, with the screen off. In doze mode network access and and CPU-intensive services are restricted.
Periodically, the system exits Doze for a brief time to let apps complete their deferred activities.
Systems exits doze mode if user wakes the device by moving it, turning on the screen, or connecting a charger.

Reference
http://developer.android.com/training/monitoring-device-state/doze-standby.html

What is App Standby?

An application goes to App Standby mode if the user does not touch the app for certain period of time and none of the following conditions happened:
  • you explicitly launch the app
  • The app has a process currently in the foreground
  • The app produces a notification

When in standby mode, network access and background sync jobs are restricted.
When user plugs the device into a power supply, system releases apps from standby mode.

Reference
http://developer.android.com/training/monitoring-device-state/doze-standby.html


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