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Updated by Riley J. Dennis on December 6th, 2016.
Everyone has dealt with battery problems at one point or another; it comes with the territory of using a pocket-sized computer. Much has been written on the topic of battery conservation — an issue that isn’t specific to Android — but there’s one important aspect that keeps tripping people up: battery draining apps.
Apps can kill your battery without you realizing it. Sometimes it’s done maliciously (e.g. smartphone malware) but more often than not, it can be explained by poor app design or an app that has gone rogue and can’t quit through normal means.
If your first reaction to this problem is to install a task killer or RAM booster, STOP. Automated task killers and RAM boosters are bad for your phone and should not be used for management of phone resources. What you really need are diagnostic apps.
Note: Wakelock Detector requires root access.
Android has built-in battery management in the form of sleeping. When you aren’t using your phone, Android will first dim the screen, then turn it off, then rest the CPU. Apps can utilize wakelocks to prevent any of that from happening. This can be useful in some apps (e.g. games) but in other cases, it’s just a waste of battery life.
Wakelock Detector is an app that checks wakelock usage history on your device, thus detecting which apps are preventing your phone from properly resting when not being used. It can tell you which apps are using wakelocks and how often they utilize said wakelocks.
The app is simple and straightforward. You can filter between partial wakelocks (CPU is on, screen is off) and full wakelocks (CPU is on, screen is on). Once you know which apps are keeping your phone awake longer than necessary, you can shut them off or uninstall them altogether.
Note: Wakelocks are a normal part of Android operation. Using wakelocks is okay; abusing them is not. Just be on the lookout for the ones that never give your phone a chance to rest.
Download: Wakelock Detector (Free)
GSam Battery Monitor
There are a lot of battery usage trackers on the Play Store, but none are as useful as GSam Battery Monitor. It’s packed with several different tools to help you manage battery life with as little hassle as possible.
The apps home screen gives an adequate quick-glance overview of battery usage according to category: phone calls, screen time, WiFi activity, etc. With the App Sucker, however, you can get a more detailed breakdown of CPU usage, including wakelock details.
The built-in charts are nifty as well. For as long as GSam Battery Monitor is running, it will track details like battery temperature, phone signal, and rate of battery consumption.
The app can be used on unrooted devices, but rooting will give you access to more advanced stats: wakelock information, sensor data, and more. It’s also free, but supported by ads. For $1.99 USD, you can upgrade to the Pro version which removes ads and optimizes views for large-screen devices.
Download: GSam Battery Monitor (Free)
Watchdog Task Manager
Watchdog Task Manager is an old app — the last update was February 2012 — that’s so good that it remains relevant to this day. It’s one of the best tools for identifying rogue apps and it’ll come in handy time and time again, especially if you’re in the habit of trying out lots of new apps.
First and foremost, Watchdog is NOT an automated task killer. It doesn’t haphazardly kill background apps simply because they’re in the background. That by itself would be a waste of battery juice.
Rather, Watchdog is a monitor. It keeps track of the CPU used by all the apps on your device. Whenever it detects an anomaly — such as a spike in CPU usage — it will alert you about it and allow you to make the decision of whether to kill that app. It’s a smart, surgical solution. No brute force.
Watchdog also provides a whitelist and a blacklist. Apps on the whitelist won’t trigger an alert even if they spike in CPU while apps on the blacklist will be automatically killed if they surpass a certain CPU threshold. The blacklist is a paid feature.
Yes, Watchdog is free but supported by ads and slightly limited in features. For $3.49 USD, you can upgrade to the paid version which removes ads and unlocks the blacklist feature.
The only downside is that Watchdog hasn’t been updated in a while; it works fine, but as Android continues to evolve, there may or may not come a day in the near future when it stops working as intended.
Download: Watchdog Task Manager (Free | $3.49)
Carat has the freshest, nicest user interface of any of the apps here. It’s bright yellow color and simple design make navigating the app a breeze.
What it does essentially is track your usage for a bit and then give you tips on how to improve your battery life based on that. It uses minimal battery life by only waking up every once in a while and sending data off to Carat’s servers to be analyzed.
This is really an ideal way of allowing you to take control of your battery life.
Download: Carat (Free)
Greenify is the classic battery monitoring app used by tons of people. The app has different levels of Doze features, similar to what was introduced with Android 6.0 Marshmallow, allowing you to prevent apps from operating in the background without permission.
If you’re worried about runaway background apps, Greenify is likely your best option. It’s not a task killer and it knows better than to repeatedly kill apps that need to be awake. It’s just an intelligent way of knowing what’s going on in the background.
Download: Greenify (Free)
How Do You Detect Battery Killing Apps?
If none of the above helps, then your battery issues may not be app-related. Be sure to check out our tips for extending Android battery life to minimize drain and maximize longevity. You may be surprised by what you find there.
Is there a diagnostic app that we missed? Are there any other techniques you use to isolate the apps that are sapping the life out of your phone? Share them with us in the comments below! We’d love to hear from you.
Image Credits: glossy battery Via Shutterstock