How many apps can run simultaneously / in the background

[Commodore]

Is it known how many apps can be run simultaneously (i.e. in their suspended background state) on iPad3? I'm rather orderly by shutting them down when I don't need them or before I put the Ipad to sleep. There's probably some limit after which the apps in the "covered" bottom horizontal bar get shut down on a "longest asleep first closed" basis, or does it go ad infinitum?

 

[goofy8275]

A lot. I rarely close apps.

 

[susanlackey]

I don't really know the answer to that. I seldom close apps unless I really feel like my iPad is lagging, and when that happens I usually find I have well over twenty apps open.

Sent from my iPad using iPF

 

[biobunny]

The iPad will automatically start to terminate apps when it's low on memory (RAM, not disk space). You really don't need to worry if you have an iPad 2 or 3. The app switchers shows recent apps wether open or not. I close apps manually because I don't like swiping trough 20 pages of apps.

Sent from K48

 

[NickyD]

Lots of apps ! But, if you want to conserve battery, start closing ! I saw the camera app burns a little more juice than the other apps.

 

[Czevski]

There is an app called Carat that will tell you if an app is a battery hog so you can remember to completely close it.

 

[MattIM]

I was at Best Buy (a retail appliance/electronic store in the United States) the other day. The store had four iPads (current generation) on display. I checked all four of them and each iPad had at least fifty apps on the shelf. One iPad had over 72 apps. It didn't appear to be a problem.

 

[iJamesH]

I was at Best Buy (a retail appliance/electronic store in the United States) the other day. The store had four iPads (current generation) on display. I checked all four of them and each iPad had at least fifty apps on the shelf. One iPad had over 72 apps. It didn't appear to be a problem.

Wow thought with that many apps going there would be a performance issue which goes to show you how wonderful having all that RAM in the iPad 3 does for it.

 

[twerppoet]

Wow thought with that many apps going there would be a performance issue which goes to show you how wonderful having all that RAM in the iPad 3 does for it.

The iPad automatically closes older apps when it needs more RAM. The number of apps in the list means absolutely nothing, other than those apps were running at some time in the past, the most recent first on the list. The iPad 3 (by my brief tests) can hold about 20 moderate sized apps in RAM.

Normally, only the current app is running. All other apps are frozen in RAM and use almost no CPU. There are exceptions, but those exceptions are limited to the few types of background tasks that iOS allows, not the entire app running and using iPad resources.

That is why the iPad remains responsive.

A misbehaving app can change that, and is the primary reason for manually clearing an app from RAM (deleting it from the multitask bar). It forces the app to reload from scratch.

The other reason is that no operating system is perfect, including the RAM clean up routines. Sometimes clearing out all the RAM can help when launching a large resource hungry app, especially on the iPad 1. Restarting would do the same thing, but leaves the list intact, which tends to confuse people. If nothing else, it leaves them wondering what is or isn't in RAM. If you clean the list regularly you have at least a rough idea of what might be in RAM.


If you'd like a more detailed explanation, this is my favorite; at least for now.

Fraser Speirs - Blog - Misconceptions About iOS*Multitasking

There are more caveats and exceptions than the article mentions, and there are certainly people who feel the article is wrong in intent; mostly because they feel that iOS doesn't doesn't do a good job of cleaning up RAM, not because it isn't supposed to work the way Speirs outlines in his article.

 

[Commodore]

The number of apps in the list means absolutely nothing, other than those apps were running at some time in the past, the most recent first on the list.

Well, I think that list is not exactly a "history list", because the apps were still listed on the list of running processes (when I checked with System Activity Monitor, or something like that) - until I closed them (after which point only those with notifications enabled were there (e.g. Mail and some others).

 

[Sleaka J]

Well, I think that list is not exactly a "history list", because the apps were still listed on the list of running processes (when I checked with System Activity Monitor, or something like that) - until I closed them (after which point only those with notifications enabled were there (e.g. Mail and some others).

In most cases, any app that isn't the foreground app isn't running at all. It might still be resident in memory (so it doesn't need to reload if you run it again), but it's effectively suspended, barred from executing any code. There are certain cases where this isn't true (like playing music in the background), but for most apps it is. Whether the app is in memory or not, it will appear on the "history list" because it is no longer running.

 

[Commodore]

I was more exact when checking the process list later on, and indeed, some of the apps eventually disappeared from the list (probably as per the intervals outlined in the article link posted by twerppoet), even though they were in the hidden/bottom bar.