Reminder: You really don't need to manually manage apps for iPhone or iPad

Reminder: You really don't need to manually manage apps for iPhone or iPad

About a year ago I wrote a post explaining why you don't have to kill multitasking apps in iOS. iOS 4 had been introduced, bringing multitasking to iPhone, iPod touch, and iPad, and because Apple added the ability to jiggle and close them in the fast app switcher, some users decided to do just that. All. The. Time.

We're on to iOS 5 now, we have some new players like Newsstand in the multitasking equation, and apparently the community is just as deeply divided as ever on the issue, even developers, even Apple Geniuses. So Frasier Speirs has put together a post of his own on the subject of iOS multitasking misconceptions, and while he ultimately proffers the same thesis as yours truly -- you really don't need to manually manage apps in iOS -- he goes into far more detail about the whys and wherefores.

Regardless of how you feel, whether you think you should leave absolutely all task killing safely to Apple, whether you think you should purge every app, every time, or whether you're still on the fence, take a read of Speirs' article and give it some consideration.

Source: speirs.org

Rene Ritchie

Editor-in-Chief of iMore, co-host of Iterate, Debug, ZEN and TECH, MacBreak Weekly. Cook, grappler, photon wrangler. Follow him on Twitter, App.net, Google+.

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There are 61 comments. Add yours.

Brown Eye says:

What about if ur jailbroken? Sometimes my jailbroken iPhone 4 seems slow if I don't close all apps.

Skem says:

That is the placebo effect.

El Hache says:

It is not a placebo. I'm jailbroken and have a lot of tweaks. If I open up 8-10 apps and don't close them, my phone crashes if I keep opening more apps. I think this only applies to non jailbroken phones.

BizarreFoodie says:

Gee, you mean if you screw with the operating system, it might not work as designed? Well I'll be...

entwined82 says:

I have to clear my memory on my ipod touch and iphone on occasion. It happens jailbroken or stock. I definitely don't need to manage it more than once every like 4-5 days.
When it takes more than 2-3 seconds for my ipod touch to load up the music app its time to kill apps running. I don't care what this article says really, I know what works for me.

GeorgeDW says:

Yep, it was the same on my 3GS. No denying it, available ram would decrease, which isn't a bad thing in an of itself- ram exists to be used- but as soon as it went under 8MB or so the whole system would hang, often causing a springboard crash.

Beezzy says:

Killing the apps should only be used if the app isn't working properly or is frozen. Facebook gets that honor of being used the most lol

dawards0628 says:

I know that having multiple apps running does slow down my wife's iPhone 4 and my sons iPod touch 4G, I however am running on an iPhone 4S and have had no problems no matter how many programs I am running

dawards0628 says:

I can also agree with a basil m as my Facebook app needs to be completely closed out of the multitasking tray constant for it to work

dclaudekatz says:

Maybe I'm misunderstanding iOS, but the thought that comes to my mind is, "Why should I trust iOS to know which of my apps to kill?" If I have a memory-intensive app that I don't need any more, and another one to which I want to return, would it not make sense for me to kill the one I don't need, so as to reduce the chance the iOS will kill the other one?

Jamie Osborne says:

I absolutely agree with you D! This is an absolutely justified reason to kill apps. Why have all that memory used if you're done with it?
Like Rene, I've observed this topic come up now and then, and it seems very hip to say how foolish it is to concern yourself with such minutiae as quitting apps when it's all done for you. I've never seen anyone take the other side of the argument though and explain why it would be beneficial to do this.
Since I've been meaning to write this up for sometime I shall attempt this below. Btw, I'm the dev of some jailbreak tweaks including AppQuit (free in Cydia) which I wrote for this very reason.
The main argument for letting iOS do its thing is that unused memory is wasted memory, and iOS will quit apps when needed. Also, it's convenient to have as many apps as possible always loaded and ready to go - right?
The trouble is, when should iOS quit an app? Memory used for apps you don't require is a worse waste of memory if it could improve the experience and performance of apps elsewhere.
The reason being that iOS tries to keep all apps running until it really (absolutely) needs to close something, this means that your device is nearly always in a low - not quite critical - memory situation (unless you've recently rebooted or otherwise freed up some memory). Writing this now, a few hours after a restart, I have 12MB free out of 512MB.
Proponents of "unused = wasted" will assert this is a good thing, and to some extent it is. General performance of recent devices with 512MB won't often be noticeably reduced by leaving iOS to manage the termination of apps, but individual applications can still benefit from manually closing apps no longer needed. This is due to another, less subtle way iOS first tries to deal with low memory; it sends warnings to all apps asking to free resources before it resorts to killing anything.
This means that a well written, but comparatively memory hungry app - even one you are currently using - will release any non-critical memory its able to that is not immediately in use; in order to keep other inactive apps and games in memory. This is often very helpful, especially when most of those apps are actively being switched between and any resources discarded aren't needed again.
Where it falls down is when you want to use just a few apps - or even just one - without having it's memory use stifled by apps you're no longer using (this a common situation - see below), often causing resources (local or remote) to be reloaded. As total memory use increases, each open app will (or should*) free any resources it can, essentially defering it's own memory requirements with respect to keeping as many apps open as possible. This is ok for the apps you're not going to be using for a while, but not if the apps you are using are constantly having to shuffle data between memory and elsewhere. If memory requirements increase beyond the point where unused resources can be released, iOS will then start killing apps.
A simple app may use a minimum of say, 8MB; others, such as games, may use five times as much. That's a lot of memory that's unusable elsewhere until the app itself quits - which won't happen automatically until all apps have already freed up as much as they possibly can - by which time, performance of apps being used has already been impacted.
*Apps with large memory requirements, unable or unwilling to free resources (such as games) worsen this situation.
If you use a lot of tabs in Safari you've most likely experienced this as the reloading of those tabs you switch back to after a while. This is due to Safari being a good iOS citizen and releasing memory for tabs not currently being viewed when asked to 'help out' via a memory warning. This could have been avoided (and the tabs kept in memory) if the apps you didn't need had been quit before a warning was triggered, allowing Safari - and any other apps still open - to keep a bigger slice of the pie for their own use.

Jamie Osborne says:

The other reason you might quit some apps is to ensure those apps you do want kept in the background aren't killed off in lieu of the ones you don't want kept.

BizarreFoodie says:

If you're going to write comments that are three times longer than the freaking article, start your own blog!

Erik says:

Oh God, not this BS again. Look, regardless of what you think when a app is "frozen" in MEMORY it uses up RAM. As available RAM goes down the performance on your phone will decrease. If you have multiple applications open and go to start, say, Infinity Blade 2, it may crash. Why? Because there is not enough RAM available so it closes the application to preserve said RAM. Eventually iOS will close out older running applications to get more RAM. You are correct if you say: "You don't need to manage your applications if you don't want your phone running as fast as possible." Otherwise, your dead wrong.

Log93 says:

There's an app out called Kill (69p) in the store that does what the name says, by mass deleting the frozen apps.
It seems to work. Still think it should be part of ios5 though ...

nottooloud says:

Kill does no such thing.
Read the comments.
It simply lists memory usage.
Remove Background on Cydia does,
however, clear apps from RAM.

Jacken says:

Sometimes apps that use the gps gets stuck, like Waze (which otherwise is an amazing app) and use excessive battery. Then killing the app is the only thing to do.

taharka says:

Yep. Waze is the one app I make sure to manually close when done. I think it's designed to continue doing stuff in the background (like monitor your speed in traffic even if you're not actively using it for navigation). Love that app, but I make sure it's closed when done since it has had its way with my battery on more than one occasion.
Other than that, I tend to let iOS do its thing.

Avenged110 says:

Haha I have like OCD friends when it come to that stuff. One like always quits every app just for the hell of it and the other clears his Recent Calls after every single call. I have a habit of closing any non-native app except tweetbot. Otherwise, its gone. Also, I have noticed some intense lag if I don't quit certain apps (like games) over time. Sometimes it does lead to springboard crashes, even on iPhone 4.

DarkClown says:

What crap!
Well okay ... On my iPhone 4S I probably never (or at least seldom) need to close Apps in the bar. But on my iPad (1st gen) I have to regularly close all the apps AND run a utility that frees memory or the whole things will slow to a crawl and eventually crash.
BTW this wasn't such a problem with iOS 4. But it seems like the first gen iPads simple do not have enough RAM for iOS 5 to work efficiently.

Steve says:

Same here, 1st gen iPad is unreliable, therefore you need to quit some apps.

Damien Otis says:

Less ram available doesn't equal degraded performance. Performance doesn't go down as there's less free ram. If you think this is the case you don't understand how computers work.

Kevin M. says:

This is completely wrong my friend. Less RAM does quite indeed equal degraded performance. Before you start to say I don't know what I'm talking about, I'm quite well versed in computer hardware and building computers, and software and programming.
Three reasons I have to disagree with this statement.
1) RAM is mainly used for storing items that need to be recalled quickly, the more of it you have, the more you can store, and therefore the more efficiently your computer or device can run. Being able to store 4GB of needed information on 2GB of RAM is obviously impossible. So if a CPU needs to store 4GB for all of its tasks at hand, and the computer only has 2GB, it first has to pull information from the hard disk, store that information to the RAM, then recall it, only to have to keep doing this over and over because there isn't enough space, causing a slow down (or throttling of data if you will). If a computer needed 4GB of RAM for all of it's tasks at hand and had 4GB+ of RAM, it could store everything needed one time, then just pull from the RAM which is faster than spinning up the hard disk every time it needed to get new information.
2) As an architecture major I do my fair share of rendering perspective views of buildings and other projects. Most rendering programs do the bulk of their work between the CPU and RAM (oddly enough most don't use the GPU as an added boost - poorly written programming but that's for another discussion). I did most of my renderings on an Intel Core 2 Duo processor running at 2.0 GHz with 2 GB of RAM (stock configuration for this laptop). After a few semesters of taking hours to render, I bumped the RAM up to 4GB, rendering time was cut by at least 40-50%. CPU and, for all intents and purposes of proving this point, GPU stayed exactly the same. Proving that more RAM actually does have an effect on performance. I have since stepped up to a MacBook Pro with an i7 quad-core at 2.2 GHz and 8GB of RAM and the renderings are finishing in around 4-5% of the original setup's time, which proves that CPU performance has more of an effect than RAM, but RAM still has an effect nonetheless.
And my third point is one that less computer savvy people can relate to. If RAM didn't matter for computer performance, why would program manufacturers (games mostly) say that the minimum requirement is 2GB of RAM, but the recommended is 4GB for example...? If RAM didn't matter, this spec wouldn't change in the overall requirements.
I'm sorry my friend but I feel that you're the one who isn't quite sure how computers work.
P.S. if RAM really didn't matter, why would VRAM (found on the GPU) need to be increased for more intensive games?? If RAM really didn't mean anything for performance, wouldn't we still be in the 32MB range for RAM and GPU's? Why do nVidia and ATI GPU's now have 1GB+ on board and are recommended to run the latest BF3, etc....?

TumnusMr says:

iOS devices are not quite structured like full computers so your comparison is not really valid.
What causes slowdowns on computers is an application or the number of applications running outstripping the amount of RAM, which starts using the virtual memory on the hard drive. It is the reading and writing to and from the hard drive that causes the slow downs.
With iOS devices the RAM is all you have. An app has to fit into the available RAM otherwise it has to start unloading and loading things into RAM as required.
When an app is loaded but there is not enough RAM, iOS will select and old, idle app to remove it from memory as appropriate to make enough space.
Apps that crash due to lack of memory are not written properly and are not announcing to the OS how much memory they need properly. Similarly apps that continue to run in the background when you are done with them are also written badly.
So in theory you should never have to close an app manually, but there are a few circumstances where it makes sense.

Erik says:

Not like a computer? iOS is based on Mac OSX code...iOS is a stripped down version of Mac OSX. Android is based off Linux; these Smartphones are like computers.

TumnusMr says:

I didn't say that they are not like computers. I said they are not architectured quite like computers as most people know them (I.e. full desktop computers). iOS devices manage memory differently from desktop/laptop computers period. Adding RAM to a desktop/laptop generally reduces its need use virtual memory, which is what speeds it up. iOS just removes stuff from RAM when it needs it (which is a lot quicker than paging RAM contents out to disk and back again like a desktop computer with too little RAM does). Thus for the most part manual memory management in iOS is unnecessary.

mtv757 says:

bro i dont think you understand how a computer works. let me give you an example. i have a 6 year old desktop. 1.8ghz dual core with 1gb of ram. for the last 3 years it has been running slow as balls. with 3 reinstalls of windows xp(to wipe clean the hard drive) still no increase in speed. i almost went to buy a new computer when i saw that there was a sale on 2gb sticks of ram. i bought a total of 8gb. now my computer runs faster than my 1 year old laptop. i no longer see a need to buy a new computer for a little while longer. now if that is not an improvement in speed in performance due to more ram then i dont know what is.

julio says:

Disagree with article.

Grandmasterflash says:

No where in any of everyone's conclusions do they say if they just finished opening up X apps in a row. The multitasking is designed to quietly turn unused apps into simple bookmarks or pointers on the taskbar. However, you cannot tell the difference between an active app versus a 'bookmarked' app on the taskbar. To truely see what of your apps are active, you'll have to take a look at the Processes icon within SBSettings...or something thereof.

9thwonder says:

i have noticed that an app or two sometimes doesn't update information sometimes unless you kill it and restart. It was a finance app that wouldn't update the companies in my portfolio unless i closed it.

DARK_BLU says:

If the apps would actually close automatically at some point, there would be no need to manually close them, but they don't. I've not had enough apps open to slow down my phone yet, but when I discovered for the first time that more than ten apps I had used were still open, I started manually closing them when not in use. There's no reason to keep a bunch of apps open that you aren't actually using, in my opinion. Not for me, anyway. A couple that I use frequently, sure, but every app I've used during the course of the day doesn't need to just be kept open, when not in use. Apps open quickly enough that that there's no advantage to just keeping apps open to get back into them. Not for me, anyway.

Geno says:

You're not getting how it works. Just because you see an app in the quick switch bar doesn't mean it's running. iOS automatically kills apps for you. For example if you reboot your iPhone all apps are reset. However you will still see them in the quick switch bar.

taharka says:

Not all apps are closed. Waze will continue to do stuff in the background and kill your battery unless you close it.

TumnusMr says:

Waze is badly written then. If you're done with a GPS app it should stop using the location services and hence go into suspended mode. For instance TomTom stops using the location services once you reach your destination or if you clear the route and exit the app. Otherwise it keeps running in the background as you would expect.

Carioca32 says:

There is no need to manage apps because iOS does not "multitask", it does a faux-multitask a la Windows 3.1, where it effectively quits the app and stores it state in memory, where it can be retrieved on demand. It was NOT multitasking then, and it is still not multitasking now.
If iOS truly multitasked everybody would have a real need to close apps all the time.

Saed says:

I disagree with the author of this post. Obviously he/she has never used an iPod touch 4th generation or an iPad 1 on iOS 5. Both become unusably slow unless apps on the multitasking tray are killed regularly.

Gregz0r says:

Either way, wether you like to quit apps, in an OCD frenzy, or not, it doesn't matter, whatever the user is comfortable with.
I mean, it's not like the old Windows Mobile Task Manager, where you could accidentally kill critical system apps.

Ricardo says:

When you jailbreak and use sbs settings and turn on show memory left you can see a direct drop and increase of memory when managing apps manually, if don't believe this try leaving opened more than 12 apps like waze, Im plus , and I tunes on a pre A4 device and you will se a drop in memory and in actual performance. Don't take my word. Try it yourself, with the 4s you rarely notice it. But trust me it happens. Because the memory used to run the app was never properly or fully flushed. and nice article. :)

techmom#IM says:

I usually ignore the app switcher thingy until I have a problem. Though I will kill of apps that think they should be running in the background (music and traffic apps) and I will also close down a bunch of apps if I am going to open a big memory hog that I know may crash.

stewm says:

That's interesting that you say that Rene, my iPad 2 regularly gives an iOS generated warning telling me to remove apps because it is low on memory.
If iOS is asking for that then surely that is contradictory to your statement. Since my phone never was jailbroken, is not jailbroken and never will be jailbroken surely that implies that Apple through their operating system is implying otherwise. In fact it goes further, it doesn't just want me to shut down a few of the apps, it wants to clear them all to free up memory.

TumnusMr says:

I think that warning you get is due to lack of storage, not lack of RAM. I don't think iOS has a warning message for lack of RAM because it will always clear enough RAM for an app being loaded if the app tells iOS how much memory it needs correctly.

Ben says:

Well, I still think the best aaagntvde Android has over iOS is the lack of iTunes and the ability to share and put files on your phone from anywhere.

Steve-O says:

In theory, yes, this is how iOS is meant to work. But in real-world practice, in my experience, it just isn't the case.
With my iP4 (on iOS 4 & 5 betas) & now my iP4S, I notice significantly increased battery drainage if leaving apps running in the background. I've tested this myself on 5-6 occasions (although not scientifically), & as a heavy/regular user & someone that knows their phone, I can definitely see the difference.
On a typical day with just 10 or so basic apps left open (albeit frozen) in the background, I'll get home from work with about 60% of my battery left. If I leave numerous other apps open in the background (such as social networking apps, news sites, an IM app & maybe a couple of other random ones - none of which are voip etc), I'll get home with about 20-25% left if I'm lucky.
Bar the basic apps that I use most regularly & want to open as quick as possible, I have to manually kill any other apps that I've used to ensure I have enough battery to get me through the day.

PreMaster says:

Actually I found some bugs in certain applications dealing with iOS 5 that I do need to close them out. One bug is if you take over 1000 pictures within the 30 day span and then once you reach your iCloud limit, it will keep trying to upload past 1000 to 1001. Watch your phone do this while it keeps cycling and trying to upload the 1001 photo. After watching this for 10 minutes your battery drops 10 percent.
I found about 20 other apps with similar bugs such as this that i can reproduce. so yeah sometimes you gotta close that stuff out.

not says:

While I agree that what this guy wrote may be the "standard" of how iOS is supposed to work on paper, real world experience has taught me otherwise. I cannot tell you how many times I've run into people who tell me that they're trying to install a new app and all it does is sit in the Waiting state. This doesn't happen all the time, but it does happen. In such cases, closing out a few apps they have in the multitasking ribbon all of a sudden frees up enough memory to change the state of the waiting app to downloading and installing. Now, when you have that waiting app in the waiting state for over a few hours and then all of a sudden it starts downloading and installing normally after you close our some apps from the background and this is something you do EVERY time this scenario happens and it FIXES the problem. That cannot be conincidence. Maybe if it happened once or twice, but not EVERY SINGLE TIME. Because of this, I don't buy the "book version" of what the guy writes about. Like I said, things should happen by the book, but being in IT for over 17 years has shown me that NOTHING hardly goes by the book. Those that expect it to and cannot think outside those confines to resolve issues FAIL in this job field. You simply cannot deny what happens when you actually observe certain behaviors that shouldn't have happened if the book was right. Another good example is when you see the constant reviews for a game or large app that says it crashes all the time or it won't start. Guess what... it starts and doesn't crash all the time if you don't have all your other crap running in the background. Why? I don't know... maybe it's bad iOS coding, maybe it's bad coding of all the other 3rd party apps you have that Apple hasn't checked with a fine tooth comb prior to putting them on the AppStore (always happens, don't kid yourself). What I do know is that while I do subscribe to what the guy wrote for the base understanding aspect of the discussion, I have my own rules I follow when a problem arises. With each problem that causes an app to not start correct, not install correctly, crash, etc. the one known solution has always been to fully terminate some of the apps that are in the background.
One MAJOR point I'd like to mention here is that the apps I do terminate in the background are ALWAYS 3rd party apps. Never once do I find myself terminating any of the core iOS apps to fix one of these other issues. What does this tell me? Simple, what Apple has written in the book for everyone to follow when they write an app, ISN'T followed by EVERYONE that writes apps for iOS, regardless of what they'd like you to think. Because of this, we ARE required to take the blinders off a bit and think outside the confines of the book rules they may have written, no matter how much the code behind it tells us it should behave in a certain way. In the end, it simply does NOT.

SkydiverTilt says:

It really depends on who the user is.  If you are one of those occasional Angry Birds, email, and safari fact checker at dinner then this article will ring true (although most likely if you took the time to read it, you are not that type of user).
However, if you constantly open 20 MB+ pdf's in Goodreader, push huge file from email to Air Sharing Pro, edit large videos and photos, walk and join telecoms while downloading and transfer the deck into a good PPT viewer, power game: talking GTA3, Infinty Blade 2, Order & Chaos, play pandora while using TomTom on the way to work...basically changing and upgrading your iPhone every single year cause it is just a plain wore out smoking pile of glass and metal incapable of surviving the next round of developer RAM and size upgrades; then this article will be a joke.
The fact is is that while iOS may do what the article says, it doesn't do it fast enough and too many apps in the trey can play havoc on RAM intensive applications.  They will crash on startup and then you have to start over.  Worse is crashing in the middle of a process (I.e. the app works on startup but when you surprise it with say a massive PDF it's crash central and you have to start fresh to get back).  For power users you have to preempt this behavior and not give iOS the choice.  
Most users are right between these two extremes somewhere and this article may mean a little or a lot depending.  Of those who are power users it's pure naivety.
@jeremy_ulima  

Jerry says:

Hah, I love how everyone that says "You NEVER EVER have to close apps" always follows their statement by "EXCEPT if you run Audio programs, apps that use GPS, apps that run in the background, apps that lock up, etc". Hah, that's like saying you only need to close apps on days that end in "y". LOL

Michael says:

Exactly! All these articles say "You don't need to manually close apps!" then go on to say "EXCEPT..." or end with "You almost never need to manually close apps"...key word: "almost"

Brad says:

Sure, you don't HAVE to close them all the time, but it makes the phone slow after you leave every single app open. It just causes more problems. When people ask me why their phone keeps messing up I tell them to clear the multitasking bar and it magically fixes the issue. That, or I tell them to turn it off and back on. And even though people claim it doesn't drain the battery because the apps are "frozen", are wrong. I tested it going a whole day with every app open compared to them not, and it obviously was when the multitasking bar was clear and nothing was open.
So I disagree with this.

flynblu says:

Cobra Radar Detector is an app that must be manually managed (a triple whammy - GPS, Bluetooth, and external device monitoring). Even though you press the Home button, turn Bluetooth off, and even though the external radar detector may be off, the app is not written well enough to allow it to move to Suspended or Not Running. It will keep looking for Momma in the background and suck the battery down very quickly. The app must be shut down with the multitasking bar or the battery will not last the day. Therefore Mr. Speirs summary statement that "Put simply: you do not have to manage background tasks on iOS.", is incorrect as there are many exceptions (as he intimates in the text). His last statement is the most important: "The system handles almost every case for you and well written audio, GPS, VOIP, Newsstand and accessory apps will handle the rest." The problem is that many third-party apps are not so well written.

Daniel Pinho says:

Thing is, some apps are barely there, others not there at all. But others DO keep running heavy processes in the background, such as Skype. So, you'll never know. Kill them all and avoid it, that's my opinion.

garylapointe says:

It makes me cRaZy that after a power down and then powering back up that I still have "apps" running in the tray. At least kill them to make me feel better about it....
Garyhttp://GarySaid.com/

grumpguy says:

Try leaving Golfshot GPS and Magellan Roadmate running in the background and see how long your battery lasts.
Both are great apps, but their GPS functions still continue even in the background.
Maybe in theory you shouldn't have to kill an app, but in reality....

mtv757 says:

all i know is that they need to changed this so called multitask setup. when i first got my 4s being new to iphone i had no idea what i was doing. i was downloading apps and testing them out. before i knew it the phone was becoming unstable and slow. apps would close out randomly. the phone would freeze. then my wife told me about the so called multitask setup and i had like 20 apps open. after i figured out how to close them all my phone started working fine. if only they could just make a card type set up similar to webos or blackberry playbook then it would be much more convenient to swap and close unused apps. looking foward to it in the new update.
p.s.
why does my phone make all these noices and when i look in it theres nothing on it. it drives me nuts....

Allison acres says:

Well rene guess I'll just listen to navigon tell me I have arrived at my destination all day bc I don't need to close the memory/battery intensive gps app that specifically states in their FAQ to "please remember to force quit when gps guidance is no longer needed" what a tard to make such a blanket statement.

cavintel says:

This whole debate and especially the referenced article just goes to show that iOS doesn't truly multitask. I kill the apps in my "multitasking bar" becuase I don't need the clutter. My children get a hold of my iPhone or iPad and open every game app under the sun. So when I double tap the home button, there are apps for DAYS on the stinking bar, none of which I want there since it is supposed to be used to be able to quickly switch between the most used apps. This just isn't the case. It should be called the "recently used apps bar" which is a much more accurate description and honestly kind of useless. I think Apple should allow you to set favorite apps to appear in the "yet to be appropriately named bar", then it would be more useful.
Don't get me wrong, I'm a fan of iOS...(and a convert from webOS) just not a fan of the way Apple has implemented this particular feature they try to sell as multi-tasking.

FateCreatr says:

I have one app, iCatcher (podcast downloader/manager) that is a HUGE drain on the battery while running. I always have to turn that off.

Lewis Zephyr says:

Install DungeonRaid game. Run it up once, your battery will be dead before half a day is up. Great game, but continues to run processes. Words with Friends is not as bad, but does run it down.
In the end, like all software. If its coded well, it will release processes when they are not needed. If not, it can be quite the pig.

Dark_Blu says:

Maybe other people's iPhones work differently, but if I don't manually close apps, they keep running, and there is no need to keep every single app that I have open running all the time. I keep the apps I most often use open. Anything else I don't need actively running, I shut down and and very much appreciate that I can do that with my iPhone. I couldn't do that with Android and over time, that ate up resources (active memory). Do what works for you. What works for me is closing apps that I simply don't need running.

RaiderWill says:

I just purchased an iPad Mini and I am amazed at how well it iOS 6 controls everything.. I have no need to shut down apps even with the Mini only having 512 megs of Ram.. And the speed is superb... I also own a Galaxy Note.. and there is NO WAY Android could work this efficiently with only 512 megs of Ram.. iOS 6 just works..