Apple announces multitasking for iPhone OS 4 (iPhone 3GS/iPod touch G3 only)

iPhone 4 event multitasking

Apple today announced support for multitasking in iPhone 4.0, which go to developers today and the public this summer. CEO Steve Jobs admitted Apple wasn't first to market with multitasking, but like with cut, copy and paste from iPhone 3.0, he thinks Apple's implementation is best.

Multitasking will be supported for iPhone 3GS and iPod touch G3 (both released in 2009) but not previous generations like iPhone 2G or iPhone 3G due to hardware limitations. (Presumably it will run just fine on an iPhone G4 this summer...)

In terms of the UI, double-clicking the home button raises the current window and shows you actively running apps in the dock. You can scroll through those apps and rapidly switch between them. State is saved so apps appear persistent to the user. (For example, if you leave a game and come back, you no longer start over -- you start where you left off.)

Inside, Apple's SVP of iPhone Software, Scott Forstall explained they looked at existing apps and distilled 7 services those apps needed to run in background, then provided them via API. According to Apple, these are:

  1. Background audio - Allows your app to play audio continuously. So customers can listen to your app while they surf the web, play games, and more.
  2. Voice over iP - Your VoIP apps can now be even better. Users can now receive VoIP calls and have conversations while using another app. Your users can even receive calls when their phones are locked in their pocket.
  3. Background location - Navigation apps can now continue to guide users who are listening to their iPods, or using other apps. iPhone OS 4 also provides a new and battery efficient way to monitor location when users move between cell towers. This is a great way for your social networking apps to keep track of users and their friends' locations.
  4. Push notifications - Receive alerts from your remote servers even when your app isn't running.
  5. Local notifications - Your app can now alert users of scheduled events and alarms in the background, no servers required.
  6. Task finishing - If your app is in mid-task when your customer leaves it, the app can now keep running to finish the task.
  7. Fast app switching - All developers should take advantage of this. This will allow users to leave your app and come right back to where they were when they left - no more having to reload the app.

Pandora said it took 1 day to recode and enable background in their app. Skype is also shown (which may explain their delayed 3G launch?)

Overall, it appears like Apple has once again abstracted a concept from low-level and developer-centric to higher level and OS-managed. Like Grand Central does for multi-core dispatch in Mac OS X, or CoreData, CoreAnimation, etc. do across Apple's platforms, it does the heavy-lifting and tries to maximize user experience at the same time.

Our question for you is, does this beat Palm webOS cards or Android multitasking? Is it enough to make you happy?

Pics and video after the break, or read our complete iPhone OS 4 preview for more!


YouTube link

iPhone OS 4 beta 2 f

YouTube link

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Rene Ritchie

EiC of iMore, EP of Mobile Nations, Apple analyst, co-host of Debug, Iterate, Vector, Review, and MacBreak Weekly podcasts. Cook, grappler, photon wrangler. Follow him on Twitter and Google+.

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Reader comments

Apple announces multitasking for iPhone OS 4 (iPhone 3GS/iPod touch G3 only)


So this probably won't drain battery as badly as Backgrounder, because only the services that need to be running when an app is in the background will be running. And switching will probably be quicker than with Proswitcher. It sounds like they've done this right, but I hope this isn't the only major feature in 4.0.

I have to laugh every time Apple comes out with new software. Is it really new when most things are already done with that method that many shun? I love Apple but way to fool people. It's like Christopher Columbus discovering America. Sorry Steve, we were doing this already :)

I hate to say I told you so, but I told you so: iPad release with iPhone app compatibility and new iPad apps, then iPhone OS update announcement with multitasking.
I don't hate to say I told you so, actually.

3GS only? Why? I mean... Backgrounder on a jailbreaked iPhone 2G works fine, what hardware limitations?

Yeah. I'm AMAZINGLY PISSED that this won't work on the iphone 3g. So, limit the number of apps I can multi with. I'm okay with that. Just give it too me you ass hat.

We went through the same thing with some features in 3.0.
Apple-is-good-way-of-looking-at-it: Apple did not feel the 2G or 3G could run with satisfactory performance.
Apple-is-evil-way-of-looking-at-it: Apple held them out in a pure money grab to force people to buy new phones.
Expect a ton of posts like these :)

Uh 2G/3G iPhones didn't have Multitasking when you bought them, did they? So why all the fuss?

Have to wait before I judge on this. Out of everything in 4.0 this is about the only thing I actually want.


Uh 2G/3G iPhones didn’t have Multitasking when you bought them, did they? So why all the fuss?

Neither did the 3GS.
Really, kid, grow the hell up. People buy upgradeable software based devices with the expectation that they will be upgraded over time with new software. Your argument is old and weak. Its the same argument used to justify no copy/paste, no mms. Give it a rest.

I have a question, does this mean I can run IM+ or some other chat software in the background?
Can I can be connected all the time?
Currently push notifications suck because the software has to launch again and re-connect to the server. If I was running in the background, then it is just a matter of bringing the app to the foreground and I can chat with whomever, no waiting.

What do you mean the computer I bought in 2008 doesn't play modern warfare properly! You mean I have to buy new hardware when my stuff gets outdated! This is rediculous. Stop complaining and upgrade!

My question is will you be able to reply to text message without exiting the app? Will that be a feature of the multitasking?

On the face of it this multitasking sounds like a very good implementation, but I can see situations where we may realise its not all we need e.g. the examples of instant messenger and text message app switching above. Will have to hold out to see it in person before we really know tho

there's still a lot to know about multitasking since this isn't true multitasking...
from a developer standpoint, this is weird.

In fact, I also predicted that the 3G wouldn't get multitasking for performance reasons, based on reports of how well jailbroken iPhones were performing with multitasking. It sets a precedent for how long Apple expects to be able to support new features on older iPhones.
The 3G was released 2 years ago this summer, so people who bought it with 2 year contracts are up for a new phone this summer anyway.
Finally, let me add that I think it's funny how people keep predicting a front-facing camera and it keeps not showing up.

I think that this may be one of the best ways that Apple could have implemented multitasking without seeming as though they copied WebOS etc. I can't wait until the new iPhone comes out so I can upgrade my 3G to something faster and better! This is the update I needed to see to stay with the iPhone and I'm pleased.
On a side note, the people complaining about not being able to use your 3G with the 4.0 OS are getting annoying! The same thing happened last year with the original iPhone and it's to be expected because technology is ever changing and let's face it, the hardware in the 3G is somewhat outdated...

Not sweet, now the value of my 3G has greatly fallen :(
It's really unfortunate that they're leaving behind the 3G folks and couldn't come up with a way to implement multitasking.

I am pumped about this "added" functionality. I used to have a Pre and really miss the universal inbox and calendar and the stock multitasking. I must admit, I really like the way they handled the multitasking with the app icons at the bottom of the screen... very nice! I can't wait. I was hoping we'd get something until then, but I'll be patient. I wonder what else will be added. It didn't get any buzz, but I saw the 5x zoom on the slide. I hope they will post a full list of all of the new features before the June meeting. No SBS-Settings type program was mentioned, but I hope it'll be there by the time it is released.

This is very similar to the way Android handles multitasking... you can't close the apps..
but at least Android has apps for that ... Iphone SDK doesn't allow for such apps

need to kno!! will this prevent that annoying wait everytime i launch meebo, ebuddy im+ or beejive?!! it drives me mad and its the only reason i want true multitasking any thing else is good enough with a saved state imo....please apple let im apps run in the backgroud push notifs are gayyyy

@jerry the new sdk has 1500 new api's hopefully theres one for that... lmao who am i kidding this is apple they will never allow that but yew can close apps probably in one way or another....

It's great and all but did they mention how/if this will interfere with the current settings for double home button taps? I have it set to bring up the iPod and I don't want to get rid of that option all together. Any word on that?
Also, I went from iPhone EDGE to 3GS. Not getting all the functions of an upgrade (if an OS upgrade at all) is nothing new. Sucks to be getting the same response from people on here that I was getting from you huh? :)

Yep, looks like I'm heading to Android... If I have to pay a penalty to upgrade -- might as well pay it and go where I can have my calls ring through --

Well that sucks! No multitasking for the iPhone 3G? Guess I'll have to wait until next year when the contract runs out. (f***ing Canadian wireless carriers)

if i double click for the app switcher , how will i quickly change songs with the ipod shortcut which uses the same process ( double click )

the reason apple took out the double tap for music controls feature is very very simple...this multitasking is only for newer ipods and iphones....and they come with the headfones with the remote that does this...all the other models should retain this feature tho..

Palm Pre troll here, I look but rarely comment on other forums, but this one is starting to bug me. I have a release day pre,which i've never had to upgrade to get the newest updates, but I sure as hell would. Probably not at the rate WebOS releases updates, but probably an annual thing. What all you people bitching about not getting updates to your older phones, try and think about how much more you'd be bitching if your phone lagged more. Or worse, try and think of how crappy this phone would be in a few years if the new software had to be able to run on old hardware. technology moves too fast to be held up by outdated hardware,and to keep in the game, any company that wants to move forward is going to utilise their options which will suit the and their customers most.
if your phone works for you now, you don't need multitasking (uhem...cough...cough), if you need multitasking, get a pre.....or,i mean, upgrade your damn phone! People that want a phone that utilises the newest technologies shouldn't have to wait for you. Sorry, but better software usually requires better hardware, you don't have it.

what is the "Ipod out' feature all about?... that is the most unknown feature that is listed in the 4.0

Steve's serving up more kool-aid for y'all. This isn't real multitasking (like on WebOS) but multitasking-lite. And, I feel for your horrendous notification system. I for one could never fathom having to connect up to iTunes every time I wanted to grab audio, video, or upgrade my OS. The Pre does all the software installs and upgrades over the air, and the cell acts like a USB drive so just a matter of dragging and dropping with full transparency.
Is it any wonder then the Pre Plus topped the field in last week's Battle of Smartphones? [
If you read the messages, it goes to show how enthusiastic the WebOS homebrew community is. Palm actively encourages tinkering under the hood and gives us full-access to the internals out of the starting gate. And, we don't have to jailbreak our phones just to squeeze out basic locked functionality. We can patch and go as we please!

I have to say, this isn't really multi-tasking is it. My guess is their hardware can't handle it (despite the 3GS's hardware being better than the Pre Plus, which handles full multi-tasking). Says something about the iPhone OS doesn't it. I guess they're waiting to get new hardware out, if iPhone G4 doesn't support ful multi-tasking they'll be dead in the water. I hate to say it, but if Palm gets its hardware right next time, sorts out its ad campaign and keeps releasing updates at this rate, they're going to pose a serious threat to Apple...

I'm running the beta right now. Once you press the Home button with an app open, it goes into a paused state. To actually close the app, bring up the list of apps running (double press Home) then hold your finger on the icon of the app running the same way you would go to move icons around on the home screen. A little minus sign will show in the top left corner of the app. Just press on that to close it. Restarting your phone doesn't close everything fyi.
Basically, Apple already put in a task manager.

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