iPad Does closing apps improve performance?

stanw

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Original poster
Aug 29, 2007
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Using a new iPad air2: when going to the multitasking option, does swiping up on the app really free up ram? Does it improve battery life? Thanks.
 

Jeff R

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Jan 28, 2014
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Theoretically, yes! I could be wrong though. I always close apps that I'm not using.
 

Trahearne

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Oct 6, 2014
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Force-closing an app in the multitasking view just further tells iOS that you don't even want it to run in the background, and IIRC iOS will shut it completely and release it from memory. Both handlers for Background App Refresh and Remote Silent Push Notification of the app would no longer be called by iOS, unless the app is manually put into active state again.

Note that Remote Silent Push is not your generic push notifications, which would never call your app for further processing anyway. Silent Push Notifications can trigger your app's routine to update contents in background, fetching new contents ahead of your active use, though like Background App Refresh it is managed by iOS based on various factors like power cost and signal integrity.

In other words, closing an app might improve battery life, but only for apps that have background tasks and have not been disabled in Background App Refresh. That's said even if you don't force close them, iOS already does a great job in scheduling them with regard to your phone's daily use.
 
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rui no onna

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Oct 25, 2013
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Improve performance speedwise? Not really. It seems to help decrease Safari crashes for me, though.
 

Altis

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Sep 10, 2013
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Killing the Facebook app will absolutely give you better battery life. Unless they've changed it, it doesn't sleep.

Most apps probably just sit in RAM doing nothing, I'd like to think. I tend to clear the ones I'm not using just so they aren't cluttering up the list, frees up some resources, and the apps are fresh when I open them.
 

saltd

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Aug 1, 2010
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I haven't noticed a difference myself. Depending on the apps you use YMMV. Theoretically, it might, but it appears that most apps just freeze when not actively used.
 

stanw

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Aug 29, 2007
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If they generally do not improve performance or battery life, how does Apple market the purpose of doing this then? How do they explain the benefits of using this feature?
 

chabig

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Sep 6, 2002
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If they generally do not improve performance or battery life, how does Apple market the purpose of doing this then? How do they explain the benefits of using this feature?
I don't think Apple says there is any benefit to using that "feature". What you're seeing is a list of recently used apps. If you want to "clean up" your list a bit, go for it.
 

NT1440

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May 18, 2008
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If they generally do not improve performance or battery life, how does Apple market the purpose of doing this then? How do they explain the benefits of using this feature?
They don't market it. It's simply a way to jump back to apps you've used recently.

Apple's developer documentation makes it crystal clear, closing background apps that are not currently running does NOTHING.
 

chabig

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Sep 6, 2002
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Here is what Apple says, "Generally, there's no need to force an app to close unless it's unresponsive. When you press the Home button two times quickly, the recently used apps that appear aren't open. They're in an efficient standby mode to help you navigate and multitask." http://support.apple.com/en-us/ht5137
 

Trahearne

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Oct 6, 2014
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For a bit more information, apps have up to 10 minutes to complete whatever they are doing (e.g. uploading a photo) when it is put into background. Upon completion or time-out, the app is in a "do-nothing" suspended state where it is just cached in memory just for quick resuming in the future. In other words, it can always be freed by iOS if necessary.

Apps also have up to 30 seconds to handle every single remote silent push notifications or Background App Refresh slot granted. However, iOS would aggressively manage these background tasks when the device is on battery. That is, the more CPU time and data the app accumulatively costs for handling pushes, or the worse the signal is, the more likely iOS will just silently drop the next turn until you put it on charger again.

There are also cases like VoIP and location services. This is just my guess, but why Skype or Facebook has reports of "draining battery" could be due to the VoIP background service, instead of their messaging service, which usually just pushes the message preview via APNS only without triggering background tasks.
 
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gardiboy

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Sep 30, 2011
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For a bit more information, apps have up to 10 minutes to complete whatever they are doing (e.g. uploading a photo) when it is put into background. Upon completion or time-out, the app is in a "do-nothing" suspended state where it is just cached in memory just for quick resuming in the future. In other words, it can always be freed by iOS if necessary.

Apps also have up to 30 seconds to handle every single remote silent push notifications or Background App Refresh slot granted. However, iOS would aggressively manage these background tasks when the device is on battery. That is, the more CPU time and data the app accumulatively costs for handling pushes, or the worse the signal is, the more likely iOS will just silently drop the next turn until you put it on charger again.

There are also cases like VoIP and location services. This is just my guess, but why Skype or Facebook has reports of "draining battery" could be due to the VoIP background service, instead of their messaging service, which usually just pushes the message preview via APNS only without triggering background tasks.
Does this also explain why there are constant reloading of apps for 1GB devices?
 

maflynn

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May 3, 2009
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FWIW, an apple genius was trying to say that my wife needs to keep doing this otherwise her phone will keep crashing - I thought that was a ludicrous statement and she went to a different apple store to get the phone replaced.

I think it can help with resources to a small extent, but I don't believe it helps with performance and I think iOS's resource management is very good so this act of closing apps, has a negligible effect imo.

With Windows phones, I found there was a much bigger effect and its something you want to do, but I've not needed to worry about this for my iPhone/iPad.
 

Mivo

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Jan 23, 2015
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Apple's developer documentation makes it crystal clear, closing background apps that are not currently running does NOTHING.
It has to do something. You can't have a list of "parked" apps, each with their last state and a screencap of the last state, without it taking up resources.
 

DoFoT9

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Jun 11, 2007
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I think it can help with resources to a small extent, but I don't believe it helps with performance and I think iOS's resource management is very good so this act of closing apps, has a negligible effect imo.
Agreed. I do find at times that certain apps seem to lock up the system by running in the background. Things such as applications that use GPS, or even Safari at times will do this and upon opening it again will reload each website.

Out of paranoia I will generally close unused applications a few times a day. It doesn't seem to make much difference to battery life from what I can tell. I even leave BlueTooth and WiFi on 24/7 and still seems fine.
 

chabig

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Sep 6, 2002
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It has to do something. You can't have a list of "parked" apps, each with their last state and a screencap of the last state, without it taking up resources.
Sure you can. The resource we are talking about is RAM. Inactive app states are saved to flash storage.
 

colodane

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Nov 11, 2012
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You should not need to close well-behaved apps. You will, however, occasionally find "rogue" apps that don't play by the rules and suck down your battery when you are not using them.

No need to be paranoid about this as long as your battery life seems to be near normal. But if you have unexplained battery drain, then closing selective apps is a good trouble shooting tool for finding the culprit. I've successfully used this technique to find a couple apps that were killing my battery life. Needless to say, they are no longer installed.

Misbehaving apps like this will almost always turn out to be newer apps from small developers. Apps with large market penetration and those from mainstream developers are less likely to exhibit any problems.
 

Trahearne

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Oct 6, 2014
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Does this also explain why there are constant reloading of apps for 1GB devices?
Yes, because when apps are in background, generally there is no guarantee that it would never be freed. Once the app is freed, the next time it is called is basically relaunching it from nothing. iOS neither has a disk-backed memory swap for inactive "anonymous" memory as on your Mac or PC, not it would preserve state for apps. Therefore, apps should implement state preservance (incl. auto-save) on their own based on their needs. Some apps actually are designed to recover the exact user state before it was put in to background, while most of the apps usually preserve only the most critical information.

But freeing other apps from memory happens usually only when the system is desperately running out of memory for the current app in the foreground. If you use only lightweight apps, the chance of such happening is fairly low unless you have really opened really lots of apps before.
 
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miamialley

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Jul 28, 2008
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Orange County, California
If they generally do not improve performance or battery life, how does Apple market the purpose of doing this then? How do they explain the benefits of using this feature?
Apps that freeze or glitch can be force-quit so they restart. My messages app and ESPN radio need to be force-closed regularly. Messages freezes and ESPN get glitchy.
 

rui no onna

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Oct 25, 2013
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Apps that freeze or glitch can be force-quit so they restart. My messages app and ESPN radio need to be force-closed regularly. Messages freezes and ESPN get glitchy.
This. Safari gets quite glitchy pretty often for me. On occasion, even force quit wouldn't do the trick and the device needs to be hard reset.
 

s2mikey

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Sep 23, 2013
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Upstate, NY
I'm not really sure but it's so easy to just "close" apps with the swipe gestus that I make a habit of doing it frequently anyways. Why not?

There are few instances where I want an app to start where I left off. I dunno.