If your Android phone is feeling a little low on battery, you can find out exactly where your battery power is going. Android’s Battery screen shows you what’s used battery power since your last charge, from apps to system services and hardware devices.
How to Access the Battery Screen
This information is found on the Battery screen in the Settings app. Open the “Settings” app from your app drawer and tap the “Battery” option under Device to access it.
The Battery screen will only show battery usage since the last full charge. If you’ve just recently charged your phone or tablet, it won’t be very helpful. Ideally, you’ll want to check this screen when your device is fairly low on battery to get an idea of what apps, hardware components, and system services actually used battery power throughout the day.
Assuming your device has been running for long enough, you’ll get a good luck at exactly what’s been draining battery power and when it happened. You can tap an app or service to view more detailed information.
Get More Advanced Battery Stats with Third-Party Apps
Android actually collects a lot more battery usage information than it displays on the Battery settings screen. Previously, it was possible for an app like Better Battery Stats to request the BATTERY_STATS permission and access this information. You could then view more detailed battery statistics–for example, you could view information about wakelocks or view battery usage for periods of time not displayed in the Battery screen.
Unfortunately, with Android 4.4 KitKat, Google removed this permission from Android and apps can normally not view it. If you’ve rooted your Android device, you can still install an app like Better Battery Stats to view more detailed information on battery usage. But without rooting, you’re stuck with the information provided by Android’s built-in Battery screen because these apps just can’t see that data.
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