Battery life is a perennial user concern. To extend battery life, Android continually adds new features to help the platform optimize the off-charger behavior of apps and devices.
Android includes the following battery life enhancements:
- App restrictions. The platform can suggest apps that negatively affect battery life, so that users can choose to restrict those apps from consuming resources. Apps aren't background restricted by default.
- App standby. The platform can place unused apps in App standby mode, temporarily restricting network access and deferring syncs and jobs for those apps.
- Doze. The platform can enter a state of deep sleep (periodically resuming normal operations) if users haven't actively used their device (screen off and stationary) for extended periods of time. Android 7.0 and higher also enables Doze to trigger a lighter set of optimizations when users turn off the device screen yet continue to move around.
- Limiting power transfer during USB backup and restore. When performing a USB
backup or restore, set the
UsbPortclass'senableLimitPowerTransfermethod totrueto disable charging and limit the sourcing power. To verify that power is limited, callUsbPortStatusclass'sisPowerTransferLimitedmethod. WhenisPowerTransferLimitedistrue, the Android device reduces the power draw as a sink to 0 (or the lowest possible value allowed by hardware) and limits the source current to 0. Limiting source power can be enforced only when both port partners support USB power delivery (PD) specification. To return power usage to the defatult state, setenableLimitPowerTransfertofalse. The default state is also returned when the USB cable is disconnected. - Exemptions. Preloaded system apps and cloud messaging services are typically exempted from App standby and Doze by default. App developers can use intents to apply these settings to their apps. Users can exempt apps from App standby and Doze power-saving modes in the Settings menu.
- Trackers. App background behavior trackers monitor apps' foreground and background battery usage to determine if the apps violate some policy.
Exempt apps
You can exempt apps from being subject to Doze or App standby. Exemptions may be needed in the following use cases:
- Device manufacturers using a cloud messaging platform other than Firebase cloud messaging (FCM)
- Carrier using non-FCM cloud messaging platform
- Third-party app using non-FCM cloud messaging platform
Warning: Don't exempt apps to avoid testing and optimizing. Unnecessary exemptions undermine the benefits of Doze and App standby and can compromise the user experience, so we strongly suggest minimizing such exemptions as they allow apps to defeat beneficial controls the platform has over power use. If users become unhappy about the power consumption of these apps, it can lead to frustration, bad experiences (and negative reviews for the app), and customer support questions. For these reasons, we strongly recommend that you don't exempt third-party apps and instead exempt only cloud messaging services or apps with similar functions.
Apps exempted by default are listed in Settings > App & Notifications > Special app access > Battery Optimization. This list is used for exempting the app from both Doze and App standby modes. To provide transparency to the user, the Settings menu MUST show all exempted apps.
Users can manually exempt apps using Settings > App & Notifications > APP-NAME > Battery > Battery Optimization and then selecting the app to turn off (or back on) optimization. However, users can't change the except status of any app or service that is exempted by default in the system image.