My phone’s anemic battery life really drained the fun away from an otherwise awesome phone, the Nexus 4. Overnight, it would typically lose about 30-50% of its battery charge – while idle! I would get about two or three hours of use before needing to recharge. Not only does a weak battery irritate the user, it also diminishes the life of the phone.

However, my battery problems went away after using a single app: Wakelock Detector. Unlike other battery analysis apps, Wake Lock Detector provides an easy method to seek out app issues causing battery drain.

This article explains how WLD identifies the apps causing your phone’s battery drain, demonstrates its use and compares it to two other superlative battery analysis tools: Carat and BetterBatteryStats.

What’s a Wakelock?

A wakelock is a mechanism within the Android operating system. Programs requiring system resources use the wakelock function to keep the phone awake. When the process finishes its task, it releases the wakelock function and the phone goes back to sleep. Wakelocks occur because an app requested the CPU’s processing power to perform a task. However, many wakelocks occur for trivial reasons, not actually related to the core functions of your phone.

Two kinds of wakelocks exist:

1. Full: Full wakelocks cause your device to totally wake up, which causes quite a bit of power drain — it fully powers on the CPU, screen (and keyboard backlight, in case you have a hardware keyboard on your device). These tend to be less common than the partial wakelocks. Even so, it still can cause massive battery drain.
2. Partial: A partial wakelock fully pulls your CPU out of slumber, although it doesn’t  power up the keyboard backlight or screen. Please note that, individually, a partial wakelock doesn’t drain as much as a full, which makes it less a threat, but cumulatively, they cause quite a drain on your battery. In fact, most users will see more drain on their battery from partial wakelocks than full ones. The more software loaded on your device, the more likely it is to suffer from a large number of partial wakelocks.

How Does Wakelock Detector Work?

Simply install the app and leave the phone alone for a few hours while Wakelock Detector monitors your power consumption. When you’re ready:

1. Fire WLD up for the first time. The first main window that displays will show two important pieces of information: First, the apps causing wakelocks. If you tap on the wakelock causing apps, you’ll see menu bar at the top of the screen. Second, if you tap on the menu button tri-dot in the upper right-hand side of the screen, you’ll find the configuration button.
2. Pay attention to the amount of time each app consumes. The longer the wakelocks associated with each app, the greater the battery drain. If the wastrel service isn’t something regularly used, it’s likely a background service that’s either improperly configured or poorly designed.
3. If you tap on an app from the main menu you’ll be presented with several options: First, you can uninstall the app via the Play Store or, second, you can open the app to reconfigure it. For misbehaving Google or system apps I suggest opening the app. Specifically, turn off the app’s access to GPS and/or try logging out. For more information on how to reconfigure some of the biggest battery wasters, check out my article on disabling Google services.

In my case, I found that two apps caused the most amount of battery drain: Google Search and Google Maps. Reconfiguring the two apps yielded another full day of use.

How Does Wakelock Detector Compare to the Competition?

Two other apps take very different approaches to monitoring battery drain: BetterBatteryStats, which requires a more technical understanding and Carat, which requires that you run the app every day. Both have their various strengths and weaknesses, but after using all three apps it’s clear that WLD provides the quickest identification process while being extremely easy to use.

• BetterBatteryStats: While offering the most comprehensive results of the three apps, its results remain inscrutable to the casual user. Chris Hoffman did a fantastic job explaining how BBS works its magic, but even with help, it takes a fair amount of reading to fully comprehend its function and how to properly optimize a phone’s battery function.
• Carat: Carat specializes in finding apps that are either horrible battery wasters or suffering from a bug, which results in wasted energy. It possesses no autostarting trigger, so you must manually run Carat over several days before it will report back accurate information on your apps. Another interesting feature of Carat is its ranking system, which awards your device a percentile rating in battery efficiency. While interesting, it lacks WLD’s simplicity and ease-of-use.

For additional apps that might help you save some battery life, check out my article, which covers alternative means of monitoring inefficient apps. Or, for more mainstream methods, check out Ryan Dube’s rundown of several highly effective battery saving apps.

Conclusion

Wakelock Detector really can help get your Android device’s battery consumption down. It’s easy to just install the app, identify the problematic battery wasting apps, then eliminate the source. While a multispectrum approach using all three apps would also provide additional efficacy, if you had to pick just one, go with WLD.

Does anyone else have any favorite battery aiding app? Let us know in the comments.