Keeping your phone’s battery alive is a constant battle. To thwart misbehaving apps and excessive drain, Google has added a number of energy-saving features to Android over the past few years. Here’s how they work, and how to tweak the settings to fit your needs.
Battery Saver stretches your charge when you need it most
Back in Android 5.0 Lollipop, Google introduced a feature called “Battery Saver” to eke a bit more life out of your phone when it’s almost drained. When you enable Battery Saver mode, Android throttles your phone’s performance, limits background data usage, and reduces things like vibration in order to conserve juice. This makes your phone a bit less convenient to use—it’ll run slower and notifications may not come through—but that’s better than your phone being completely dead.
You can turn on Battery Saver mode at any time. Just head to Settings > Battery on your phone and flip on the Battery Saver switch.
While you’re in the Battery settings, if you tap Battery Saver, you’ll also see an option to turn on this mode automatically when your phone reaches 15% or 5% battery. That way, when your device nears death, Android will attempt to stretch the battery as long as it can go before that final shutdown.
If you frequently rely on this mode, then add a shortcut to the Quick Settings panel, which you see when you swipe down twice from the top of the screen. For easy access, just click the edit pencil and drag the Battery Saver option into Quick Settings.
Doze puts your idle phone into a deeper sleep
Ever notice that some notifications seem to come through at the exact moment you turn on the screen? That’s a result of Doze, a battery-saving feature that puts your phone into a super-deep sleep when it’s idle.
When your screen has been off for a while, your phone begins dozing. Doze mode, according to Google, shuts off network access and defers any syncs. Instead, it waits for occasional “maintenance windows,” when the phone wakes up briefly, to run those jobs. That means you’ll still get notifications, but they may be a bit delayed, since they’ll only come in during those maintenance windows. So-called “High Priority” notifications like text messages and phone calls will still come through right away, but emails, Facebook messages, and other less immediate notifications may lag.
If the screen is off and the phone is completely idle—that is, sitting on a table instead of moving around in your pocket—it’ll enter an even deeper Doze state. In this mode, Android disables certain types of alarms, GPS, Wi-Fi scans, and “wakelocks”—which keep your phone active when the screen is off—as well as cutting off network access and spreading out those maintenance windows even more. This super-deep Doze mode is particularly effective at saving battery, as you can see in the graph below.
When you turn on your screen, your phone automatically exits Doze mode. That’s why you’ll occasionally see notifications arrive just as you unlock your phone—those messages came in between maintenance windows, and waking your phone up allowed them to pop up.
Android activates Doze by default, and there’s no way to turn it off completely. You can, however, exempt certain apps from Doze mode if you want them to run in the background at all times. That said, I wouldn’t recommend you do this, since it will drain your battery faster. If you still want to exempt a few apps, head to Settings > Battery, tap the menu button in the corner, and choose “Battery Optimization.”
You’ll see a list of apps that are “Not Optimized,” which means they’re exempt from Doze. By default, this list will mostly contain core pieces of Android that need to run at all times. If you tap the “Not Optimized” header, though, you can see a list of “All Apps” on your device. Then tap any of these apps to change it to “Don’t Optimize,” which will exempt it from Doze and allow it to run in the background.
The real tip, though, is to take advantage of Doze as much as you can. If you’re sitting at your desk and not using your phone, put the device face-down on the table to turn off the active display. That will encourage it to enter deep Doze mode, which can really help stretch your battery.
App Standby sleeps apps you rarely use
Ever download an app, install it, and then forget about it for a month? App Standby keeps those apps from running in the background and draining your battery. If you don’t use an app for a few days—and if it hasn’t sent you any notifications—it’ll enter App Standby, where it’s no longer allowed to run in the background or access the internet until you purposely open it again. If you don’t, then it will only run briefly once a day or so, and when your device is plugged in, before re-entering standby mode.
You can exempt apps from App Standby the same way you do Doze: Just turn off Battery Optimization for that app, as described previously. If you’re curious about which apps are currently in Standby mode, though, you can check on them from Android’s Developer Options. Just be careful, as these options were not meant for users to tinker with.
Head to Settings > System > About Phone and tap the “Build Number” seven times. Your phone will tell you that you are now a developer, allowing you to access the new “Developer Options” menu in Settings > System. Head into that menu and scroll down to “Inactive Apps” near the very bottom. Tap that option, and you’ll see a list of apps on your system. The ones marked “Inactive” are currently in App Standby mode.
As a more productive activity, though, try checking out the “Active” apps. If an app is active even though you haven’t used it in weeks, it might be worth asking why. Perhaps you need to turn off notifications for that program, or maybe it just deserves to be uninstalled.
Oreo notifications tell you when an app is running in the background
Not all apps that run in the background are misbehaving. Some need to run constantly for certain features to function. In Android 8.0 Oreo, Google added a notification that lets you know when an app is using battery in the background. That way, you can choose whether or not that app’s features are worth a little extra drain. If it isn’t, you can disable the offending feature or uninstall the app entirely.
This notification can get annoying, especially if you have an app that runs in the background all the time, giving you a 24/7 notification. In Android 8.1, you can disable this notification by sliding it to the right, tapping the Settings icon that appears, and sliding off the toggle switch. Note that this will disable the battery usage notification for all apps, not just that one.
In fact, so many people found this feature annoying that Google has already announced it will get rid of the notification in the next version of Android. But for now, you know how to use it—and disable it.
The future: Adaptive Battery learns your usage patterns
Google recently announced the next version of Android, currently codenamed “Android P,” which will deliver yet another battery-saving feature—this time with more machine learning. Adaptive Battery attempts to learn which apps you use when. Based on this information, it will restrict the apps it doesn’t expect you to open anytime soon.
Much like the other features in this guide, you don’t have to do anything for Adaptive Battery to work—it’ll just do its job in the background. You can, however, turn it off from Settings > Battery > Adaptive Battery. Android P won’t likely be available until this fall (or later, depending on your phone), but eligible users can download the beta now to test it out.