Killing Apps in multitasking menu decreasing battery life in iPhone 4?

[nph]

I was super satisfied w battery life of my new iPhone 4 the first two days and until it ran down to 1%. After that I think it decrease too much and almost 1% per minute when surfing. But one thing I might be wrong is killing apps in the multitasking menu. Will that increase or decrease battery life? I am thinking maybe it will decrease rather since it is more of an effort to reload the program then having it idle in memory. Am I wrong and what else could affect battery life? I have fixed usual suspects, brightness, location services and push services...

Could I have a bad battery?

Any insight appreciated!

 

[Julien]

Apps in the fast switch (not multi tasking) bar have no effect on battery life except for Apps that run specific APIs in the background. It's easy to identify these since an arrow or a play icon will be in the top menu bar.

 

[GFSarah]

Depending on the individual apps, I'd say it would either possibly help with battery life or it may have no effect at all. Obviously the ones that are actually doing something will drain the battery, but as far as I know, the ones using "Fast App Switching" shouldn't drain the battery. I always kill mine after use anyway (which can get annoying), but I would think that even if the FAS apps DID drain the battery, it would hardly be noticeable. Keep in mind that as you browse the web, it makes a difference whether you're on WiFi, 3G, or Edge, and also how strong your signal is. WiFi uses the least amount of power, followed by 3G and with Edge using the most. Also, fewer bars will draw more energy than full signal strength will because the phone is always trying to find a better connection.

 

[falconman515]

Apps in the fast switch (not multi tasking) bar have no effect on battery life except for Apps that run specific APIs in the background. It's easy to identify these since an arrow or a play icon will be in the top menu bar.

Thats the Google Maps app and the iPod when you get those icons (and Pandora)

If you are running games, facebook, and many other utilities capable of running in multitasking and you have a few pages in your bottom bar your battery will drop Big Time!

Occasionally open your bottom bar and close stuff you dont want to keep a better battery life.

 

[fastblack]

Thats the Google Maps app and the iPod when you get those icons (and Pandora)

If you are running games, facebook, and many other utilities capable of running in multitasking and you have a few pages in your bottom bar your battery will drop Big Time!

Occasionally open your bottom bar and close stuff you dont want to keep a better battery life.

You are wrong. They are not actually multitasking, they are in a save state which is much different.

 

[JayLenochiniMac]

Obviously if you're trying to kill apps (unnecessarily) all the time, that's more time for the phone to stay on and this runs down the battery. Leave it alone.

 

[spblat]

Occasionally open your bottom bar and close stuff you dont want to keep a better battery life.

You do not need to do this to save battery. Trust the iPhone.

http://www.technorotic.com/2010/06/...s-answered-on-the-management-of-multitasking/

 

[Julien]

Thats the Google Maps app and the iPod when you get those icons (and Pandora)

If you are running games, facebook, and many other utilities capable of running in multitasking and you have a few pages in your bottom bar your battery will drop Big Time!

Occasionally open your bottom bar and close stuff you dont want to keep a better battery life.

Incorrect, here is a link to Apple 7 APIs for iOS4. 1-5 can actually run the API in the background but will show an icon in the top task bar (so you will know it is using the battery). Most Apps (no icon in task bar) are 6 or 7 and these have *NO effect on battery usage.

* Task Finishing can have a small effect on battery usage.

 

[falconman515]

Incorrect, here is a link to Apple 7 APIs for iOS4. 1-5 can actually run the API in the background but will show an icon in the top task bar (so you will know it is using the battery). Most Apps (no icon in task bar) are 6 or 7 and these have NO effect on battery usage.

I stand corrected and apologize for misinformation. It really seems that at times when nothing is running down there my battery will last forever, but some days I look at the % and its WAY down and that normally happens when I have like 15 things running in the bottom multitasking bar.

Just seems a bit odd but facts don't lie I guess.

 

[admanimal]

But one thing I might be wrong is killing apps in the multitasking menu. Will that increase or decrease battery life? I am thinking maybe it will decrease rather since it is more of an effort to reload the program then having it idle in memory.

You are correct in thinking that this could potentially have a negative effect on battery life. How much exactly depends on the apps of course.

Assuming that none of them actually do anything in the background (audio, GPS, etc.) and that they are all compatible with fast app switching (i.e. they were recompiled for iOS 4 and don't just quit when you switch away from them), then generally speaking it is probably better just to leave them in the background. Once an app has been run once and is loaded into RAM, the OS has an optimized process for getting the app back into the foreground. Of course this is visually apparent in the fact that switching back to an app is generally faster than running it for the first time.

Again, I have no idea how much of an effect this could actually have, but it's plausible that it would have some effect.