Multitasking

[stanw]

I double click on the home button and I see TONS of open apps. I go through all of them and close them

1. Does having all these open kill my battery?
2. Are all of the open apps displaying down at the bottom technically running in the background? How does multitasking work on the 4S?

Thanks.

 

[boomhower]

I double click on the home button and I see TONS of open apps. I go through all of them and close them

1. Does having all these open kill my battery?
2. Are all of the open apps displaying down at the bottom technically running in the background? How does multitasking work on the 4S?

Thanks.

It really depends on the app. Not all of them are really open. Most apps don't actually multitask but are just in a save state of where you left off. Some things like music will stay active in the backround but most are just in savespace. It can hurt performance in that it eats up memory but not so much battery, that's why Apple implemented it this way.

 

[omgitscro]

Multitasking does take up battery, though you probably won't notice it much. It works by "freezing" the applications that you exit. Applications are allowed to run certain functions such as uploads, or even audio, until you quit them. The apps aren't allowed to fully run, they can only access the functions that Apple permits. If you really want to maximize battery life, you can go ahead and force-quit all of the apps that are running.

 

[jman240]

I tend to post this all the time heh, not mine but the most clear and concise explanation I can find.

http://whenwillapple.com/blog/2010/04/19/iphone-os-4-multitasking-explained-again/

FYI: Sometimes an app gets stuck running and drains the battery a bit. You can tell if this has happened when after a full charge you look under usage and the Standby Time is equal to the Usage Time. If you've had the phone on sleep (ie screen off) and not doing anything like playing music etc for a period of time, these numbers should be different (Standby time should be longer than usage time) so when this happens an app has become stuck and you may want to clear them all from the multitasking bar with the (-).

 

[gentlefury]

No, it does not affect battery life. It is simply a saved state.

Have you ever used an NES emulator? When you save your current state, close the application, and restart it later to resume exactly where you left off? iPhone multitasking is exactly that. It stores a snapshot of your current application so when you start it again later it will resume right where it left off. If it is extremely recent it will restore it from active memory and restore very fast....once active memory is full it will dump to passive storage in a first in last out manner. This is why you can actually shut down your iPhone and upon startup resume any app you left off.