Does Your Android Need a Task Killer App?

Android task killers were all the rage, but are they still necessary?

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One alleged way to improve smartphone and tablet battery life for your Android device is to use a task killer app. However, improvements in the Android operating system have rendered such apps largely unnecessary since you can now force-stop apps at will.

The information and apps below should apply no matter who made your Android phone or tablet: Samsung, Google, Huawei, Xiaomi, etc.

What Does a Task Killer Do?

A task killer is a mobile app designed to force-stop other running apps and background processes, which frees up system memory (RAM) on your phone or tablet. Some task killers perform this function automatically over designated time intervals, while others work only when the user manually chooses to kill select apps shown on a list.

Task killers grew in popularity as a proposed solution for extending smartphone and tablet battery life. The premise behind using a task killer is that by removing other running apps from memory, the CPU would have less to process (activities, services, broadcasts, etc). Less work placed on the CPU leads to less energy used, which means a device should last longer throughout the day.

Should You Use an Android Task Killer?

Despite the energy-saving claims made by task killer developers and users who swear by the benefits, the general consensus is that modern Android smartphones and tablets have little need for a task killer, especially since Android’s built-in Application Manager lets you force-stop apps on demand. Also, some Android devices come with a task killer such as the Smart Manager app.

While the Smart Manager may not be crammed with features, it shows how much total RAM is being used, lists all the background apps (with the amount of RAM and CPU power each is currently using), and offers the option to kick any/all apps out of memory. The Smart Manager also details battery usage and storage data.

Vocal opponents of task killers claim that such apps do more harm than good. Any app you download from Google Play is safe; however, if you install a task killer from outside of the Play Store, then you run the risk of introducing malware to your device. That said, running a task killer is unlikely to utterly destroy your device. You just may not experience much (if any) battery savings for your efforts.

The Pros of Using Task Killer Apps

There are a few ways that task killer apps for Android can be useful:

  • They can help you find apps that are steadily using up processing power for no apparent reason so that you can uninstall and replace them with a better alternative.
  • Task killers can help with apps that are constantly trying to connect to the internet and/or send push notifications, which drains the battery (especially if the device wakes and turns the screen on each time).
  • Smartphones and tablets running older versions of Android OS can still benefit from task killers since the older versions aren’t as capable with process management as newer ones.

Cons of Using Task Killer Apps

While most task killer apps for Android are safe to use, there are some potential downsides:

  • Task killers use processing power to do their job, so energy savings may be marginal at best, especially if the force-stopped apps weren’t doing anything to consume power.
  • Some essential system apps automatically restart after being forced to stop. Such situations prompt a back and forth cycle with the task killer, which ends up using significantly more processing power and battery life.
  • Most background services/processes don’t use a whole lot of memory when not actively doing something.
  • There are times when you want apps to run in the background, such as reminders, updates, messages, alarm clocks, and more. Using a task killer could lead to many missed appointments or events.

Task Killers and Other Apps for Improving Battery Life

If you have your heart set on using a task killer, there are a few good options:

  • ES Task Manager: App developer ES Global combines all the task-killing features you want along with other useful tools like a cache cleaner, startup manager, file manager, and more.
  • Clean Master: In addition to freeing up RAM with a single touch, Cheetah Mobile’s Clean Master 2017 also helps by removing residual junk files, scanning for viruses, and improving Wi-Fi security. This is the same developer that makes Android’s Smart Manager app.
  • Watchdog Task Manager: Although Watchdog Task Manager can kill background apps, its real focus is centered on monitoring CPU usage and alerting the user. Created by Zomut LLC, Watchdog lets you know when an app has gone rogue (i.e. consuming a considerable amount of power). Instead of blindly killing all apps, you can select just the out-of-control one.
  • SystemPanel 2: This app does not boost, clean, or kill any apps (the developer, NextApp, says so explicitly in the description). Instead, SystemPanel 2 offers an extensive look into everything going on in your device complete with colorful bars, charts, and plotted graphs for visual presentation. The detailed information shown for battery consumption will let you know which apps are the biggest drain.
  • JuiceDefender: Created by Latedroid, JuiceDefender has been saving battery life for years without the need to kill tasks. What this app does is manage battery-draining elements (e.g. Wi-Fi, mobile data, screen, etc.) through hibernation-like settings, schedules, and triggers. It's similar to, yet more comprehensive than, Android Marshmallow’s Doze Mode.

Why Android Task Killers Are Becoming Obsolete

Laptop and desktop computers process software/applications and manage resources differently than mobile devices running the Android OS. For example, with the Windows OS, less available memory means a slower system experience. It’s why adding memory is an easy way to boost PC performance.

Android devices, on the other hand, are designed to operate the same way no matter how full or empty the memory might be. It’s normal for an Android device to use up half or more of total available memory. In fact, having apps stored in memory often results in better battery performance. That's because apps stored in an Android's memory are essentially paused and inactive until you choose to load (basically unpausing) the app again.

Loading apps from memory is faster and less CPU-intensive than fully-loading from device storage. It doesn’t matter, really, if your Android memory is completely full or empty; battery power only gets used when the CPU is actively processing activities. In other words, just because an app is stored in Android’s memory doesn’t mean it’s doing anything to use power.

The Android operating system is designed to automatically remove apps from memory when more is needed in the moment, opting first for lowest-priority (ones you haven’t used as much). It’ll keep going until there is enough available memory to reassign and run whatever app you’ve just loaded. This wasn’t the case with the early versions (prior 2.2) of Android, which were prone to leaving apps actively running indefinitely. Back then, task killers were far more effective and necessary.

How Mobile Devices Manage Tasks

Older-generation smartphones and tablets used processors with standard-sized cores that focused on maximum power. These processors would throttle core speeds in real-time to match activities, which was not very efficient. Many of today’s multi-core mobile processors have both improved performance and the capability of intelligently handling tasks. For example, ARM (a manufacturer of mobile processors used in the vast majority of smartphones and tablets) utilizes a design that combines both small and big cores together, which results in far greater efficiency.

Here's an example: an 8-core ARM CPU features four little cores in one processor and four big cores in the other processor. When a user engages in an activity, the system decides the appropriate core size; small activities (e.g. sending a text message, opening a document, etc.) can be handled by small cores, while more intensive activities (e.g. recording video, mobile games, loading multiple web pages, etc.) would use big cores. This approach allows processes to run quickly without using excess power and wasting battery life. As such, today’s devices last longer, even if they’re running lots of processes at once.