iOS4 question about multitasking

James Hunt

Apologies if this has been covered before.

As I understand it, in iOS4, multitasking largely involves 'freezing' an app rather than true multitasking - is this correct?

Double clicking the home button shows a list of recent apps. Are the apps on that list running in the background still using up part of the 3G data allowance, or running up data charges?

Do apps need to be shut down fully to avoid this or are the frozen apps completely inactive and therefore not contributing to your data usage, thereby leading to data charges.

I only ask as, although my iPhone 4 is now up and running on 3, I have learned that my new flexi-unit tariff, which includes 2gb of data/month, won't come into operation until the end of this billing period, which is a couple of weeks away for me.

Johnzy Fitzgerald

As far as I know (never much) it mostly depends on the specific apps that you have opened.
The vast majority of them will use absolutely no data while they are paused/frozen/whatever.
However some apps such as Skype can (and most likely do) use data while in the background.
Some apps allow task completion after you leave them. Such as maybe uploading a video. So that the uploading will continue after you've left the app. However in cases such as that, all data use should end once the task in complete.
Basically though like I said, 99% of apps will do nothing while in the background.

rivalius13

There are 7 different methods of multitasking in iOS4, the most common method will probably be just freezing the app and returning it to it's previous state.

I was going to try explain them, but then I went to google:


1) Audio, so you’ll be able run audio apps in the background while using any other app (e.g. Pandora, last.fm, radio stations)

2) VOIP which mean you’ll be able to receive calls in the background. Skype call stays open and tappable at the top of the screen. Pretty neat, makes Skype on the iPhone a lot more convenient.

3) Location Now the iPhone can continue to track your location with GPS in the background and it shouldn’t drain your battery because it won’t require GPS to be on all the time, using cell towers to track your location. (I dunno, apps tracking your jogging and ****?

4) Updated push notifications (Can't remember what this one's about specifically...)

5) Local notifications: No longer need to use Apple’s servers to get push notifications delivered to you. (Apps used to have to route through Apple servers to send push notifications, no longer necessary they can do it all on the phone)

6) Task completion so you can finish things like uploads in the background. (Hit send tweet/text/whatever and exit the app and it will finish sending it before exiting)

7) Fast app switching, which lets apps sleep and resume instantly. (Freezing the app)


Source: http://thenextweb.com/apple/2010/04/08/apple-announces-availability-multitasking-iphone-40/

Different apps will use different types, all must be updated though so if your favourite game or fart app doesn't get an update to support it it will just quit when you exit, from what I gather. But, I went and added commentary in the parenthesis.

James Hunt

Depends on the type and version of the particular app so, which makes sense.