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iPad/iPhone iOS 4 closing apps

As many readers will be aware, I am an enthusiastic iPad user. This posting is to share a discovery, which I think is rather important, with other users. If you know all about closing apps on an iPad/iPhone running the latest operating system, this will not interest you. If you do not know what I am talking about, please read on…

In the past, iPads and iPhones ran iOS 3. This permitted quite rapid swapping between apps, which I thought was quite satisfactory. With the iPhone 4 came iOS 4. Other models and older iPads got software upgrades and new iPads are now delivered with this OS version. The key feature is multi-tasking. I admit that being able to listen to Spotify or TuneIn Radio while I am writing an email is cool and fast switching between recent apps by double clicking the Home button is very handy. However, the overheads of multi-tasking are significant and I cannot see why most apps need to continue running when you shift to something else. It would appear that my concerns are justified.

When you double click the Home button, the scrollable line of icons that appears seems to represent recently used apps, which you can switch to instantly. This is not the case. This is a display of all the apps currently running. Each of these is consuming resources – some CPU time, I expect, but, more importantly, using memory. I do not mean the multiple Gigabytes of flash storage; I mean the processor’s RAM, which is relatively limited. So, as you run more and more apps, you use up all the resources. If an app runs low on memory, it may misbehave and crash. This is something very familiar to Windows users, but I thought that Apple offered us something better.

There is a way to address the problem. You can shut down apps, which I assume results in their relinquishing resources. To do this, bring up the running apps display, as I described. Press and hold on one of the icons and they will “jiggle” and display a “-” symbol. Touch that symbol and the app is terminated. Click Home when you are done. I can find no other way to shut down an app or any way to shut down all the running apps or even get an idea whether resources are running low. I would be very happy to hear that I am in error.

IMHO, it would be better if the ability to multi-task could be set on a per-app basis. The user would then be in some kind of control.

Colin Walls

I have over thirty years experience in the electronics industry, largely dedicated to embedded software. A frequent presenter at conferences and seminars and author of numerous technical articles and two books on embedded software, I am a member of the marketing team of the Mentor Graphics Embedded Systems Division, and am based in the UK. Away from work, I have a wide range of interests including photography and trying to point my two daughters in the right direction in life. Learn more about Colin, including his go-to karaoke song and the best parts of being British: http://go.mentor.com/3_acv

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0 thoughts about “iPad/iPhone iOS 4 closing apps
  • iOS actually has a very elegant implementation for backgrounding, or multi-tasking. Only a handful of core services are actually available to an application before it gets sent to the background – this is very different from desktop multitasking where the app has continued access to processor resources. This type of implementation helps preserve battery life optimally, compared to other mobile OSes like Android, which I believe allow background apps to use processor resources (and therefore allow a poorly written app to drain the battery faster).

    With iOS, there is no real need to continuously shut down apps unless they are using GPS or audio services (and consequently using a data connection because of it). Frozen apps will use almost no resources, and therefore shutting them down repeatedly would simply be a waste of time.

    Ars Technica has some really good coverage of some of the details, limitations, and benefits:
    http://arstechnica.com/apple/reviews/2010/06/ars-reviews-ios-4-whats-new-and-notable.ars

    • This is good input Sameer. Thank you.
      My main point was to show how to stop a troublesome app. I have 2 or 3 that have just started behaving oddly or locked up. Stopping and restarting them gets them going again.

  • Can anyone help? I’ve searched for a solution to closing apps on my iPad 4, but the prescribed solutions do not work:

    When I press the home button twice, all of the open apps do indeed appear at the bottom of the screen. However, touching/pressing on these apps does NOT cause them to wiggle and display “-” next to them. This works for my iPhone perfectly, but not on my iPad 4. I have so many apps running in the background or “open”, that everything is slow, freezing, etc.

    Can anyone help?

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This article first appeared on the Siemens Digital Industries Software blog at https://blogs.sw.siemens.com/embedded-software/2011/01/20/ipadiphone-ios-4-closing-apps/