Task killers are ba-ha-ha-ha-ad!
Mention "task killer" on any Android forum and a million know-it-alls will call you a n00b because even your grandma knows that task killers turn your Android phone into a battery-guzzling crash test dummy of an iPhone.
Because the built-in memory management is sooooo good that you should just let every process run wild, duh!
It's not about memory
Sure, memory management in all but the oldest versions of Android is good. Unless you run Doughnut or Cupcake (Android versions used by the caveman long ago) there's no need to free up RAM. Most apps that show up in your running tasks list are just sitting silently in the background doing nothing, waiting to spring to life when you need them. On Android, empty memory is wasted memory. Not always, but most of the time.
But what if those silent background tasks are not so silent after all? What if they go online behind your back, or suck your battery dry by preventing your phone from entering deep sleep?
Facebook: guilty as charged
The worst "silent" process "doing nothing" on my phone in what's supposed to be the background is Facebook, and that's just one of its many flaws. It came preinstalled on my Motorola, but even if it didn't there'd be no escape for me. If I remove it my girlfriend will kill me, but if I just let Facebook do its thing my phone turns into an insomniac that burns
When Facebook "sits quietly cached in the background" it keeps phoning home, even with all its notifications switched off and the refresh interval set to never. Of course it does. I wouldn't expect anything else from an app that exists for the sole purpose of tracking every step you take to sell you out to its advertisers.
Facebook quietly burns many megabytes of data in the background, which is really nice if you're travelling and pay for international data roaming. And that's not all. Facebook prevents my phone from entering deep sleep. This more than quadruples standby battery drain. Yes, really. When my phone sits idle it burns 0.5% of battery juice per hour, but when Facebook is "cached in the background doing nothing" it drinks at least 2% every hour. Just think about it: if I leave my phone alone for a day I lose half my battery load just because Facebook sits in the background doing nothing useful. What more reason do you need to take countermeasures?
Of course you're better of kicking the Facebook app out of your phone and use an alternative Facebook client like Friendcaster instead (you'll lose the Facebook phonebook folder from Facebook v1.5.2 and older), but there are other misbehaving apps that are not so easy to replace.
Shazam is another reason to use a task killer. When you're done tagging music Shazam doesn't go away, but it keeps waking up to send data back home. What data and why? Shazam won't tell you. But my battery stats tell me that when Shazam sits in the background doing nothing my battery drains as fast as the gas tank of a fully loaded SUV on an uphill dirt track.
Google Maps keeps the network location service active when you don't need it. Of course you can toggle the network location service off whenever you're done with it, but unlike GPS the network location service is resistant to one-tap widgets so you have to dig into the Android settings everytime. To cut a long story short, Google Maps is an excellent candidate for the hit list of your task manager.
And there's more than Facebook and Maps. Goggles, camera apps, anything with periodic polling or push notifications that you can't switch off, there's no shortage of apps that waste your battery because they weren't taught to shut up. Anything that wakes up your phone when you want it to stay asleep drains your battery and should be assasinated. Especially if it goes online when it shouldn't.
Kill your autostarts
As any xda forum geek will tell you, killing apps doesn't make sense if they relaunch over and over again. You stop them, they restart, you kill them again, they resurrect, you shoot 'em with a silver bullet, they get up again, etcetera. You'll see your battery go up in flames if you allow this to happen.
So before you tell your task manager to go on a killing spree, you should tell your phone not to let your bad apps autostart.
ROM Toolbox has a pretty good autostart manager built in. It lets you stop apps from launching when you boot your phone, and throws in a bunch of other autostart triggers. Network change, SD card mounting, widget update, and much more.
Gemini App Manager has even more autostart triggers, and this is what I use to tame Facebook, Google Maps, and over a dozen other apps.
Choose your weapon
Now that you've decided to use a task killer to shoot rogue apps and dealt with the autostart triggers it's time to choose the right task killer. That's not an easy task, because most task killers in the Google Play Store are crap.
Most task killers use the shotgun approach. They kill all running tasks without exception, because this allows them to tell you they've freed up a billion gigabytes of memory. Totally useless, because we all know that freeing up memory makes no sense. Some task killers come with an ignore list that lets you enter a couple of apps that should not be killed, but this approach is the wrong way 'round.
A good task killer doesn't have an ignore list, and it doesn't try to free as much memory as it can. Instead, a good task killer doesn't kill anything unless you explicitly tell it what to kill, and when to kill it.
The built-in task killer that came with my Motorola phone did a good job. It didn't have many options, it simply let me enter a list of apps to be killed two minutes after the display timed out. That was enough for me. But then I switched to CyanogenMod, and Motorolas task manager refused to work there. So I had to dig up a suitable alternative from in between the massive load of crapware that pollutes the Google Play Store.
After testing dozens of useless apps that give task killers a bad name I found two apps worth trying.
Bomb That Task
Bomb That Task kills the apps you choose when your display blacks out, or after a delay that you choose. If Android plays difficult then Bomb That Task uses its root access to do what I want no matter what Android thinks of it. Another nice touch: you can tell it not to kill anything in the middle of a phone call.
Too bad that Bomb That Task didn't kill apps if I set a delay. Even without a delay it often failed to kill Facebook, the app that needs killing more than any other app. The Bomb force-closed a bit too often too. Maybe it's because Bomb That Task hasn't been updated in ages?
Fortunately I found an alternative that does the job.
Automatic Task Killer by S.Tashibana
Automatic Task Killer by S.Tashibana kills apps right after your screen switches off, or after a delay of your choice. A delay can be useful if you have a very short display timeout. In contrast to Bomb That Task, Automatic Task Killer managed to kill the selected tasks whether I set a delay or not.
Just make sure you DroidWall Automatic Task Killer offline and use PDroid or LBE Privacy Guard to deny GPS access. Wasting battery power to poll your location and to download ads defeats the purpose of an app that's meant to save your battery, so just say no to location-based advertising.
I'd use Bomb That Task if its delay option would work for me and if it wouldn't crash so much. Automatic Task Killer doesn't have these issues. So far I didn't find an app that Automatic Task Killer couldn't kill, so it's my weapon of choice for now. If you know of a better app, feel free to post a comment or hit the contact link on the bottom of this page.
Remember, task killers are only useful to stop apps from going online behind your back or polling your location or otherwise refusing to shut up when they should. Don't try to shoot apps to free up RAM, because this really makes no sense unless you run an ancient version of Android. And don't forget to tweak the autostart triggers of the apps that you kill, or else your task killer will do more harm than good.
• Bomb That Task
• Automatic Task Killer by S.Tashibana (not to be confused with similar apps of the same name)
• Gemini App Manager and ROM Toolbox
more ways to save your bandwidth and battery:
• Make your battery last longer without dumbing down your smartphone
• DroidWall keeps nosy apps offline
• AdAway because you don't want ads to drain your battery
• LBE Privacy Guard to tell apps not to hammer your GPS (among other things)
• Use Friendcaster instead of the official Facebook app