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Apple Executive Confirms: Manually Quitting Apps Doesn't Improve Battery Life (bgr.com)
An anonymous reader writes: Apple software engineering VP Craig Federighi recently dispelled one of the more long-standing myths about iPhone battery life. In short, if you spend a few minutes every day double clicking the iPhone home button and manually closing up applications in an effort to maintain battery life, you're wasting your time. The reality is that the applications you see upon opening up the multitasking pane are actually nothing more than static images intended to represent a list of your most recently used applications. Apple support documents have indicated, "generally, there's no need to force an app to close unless it's unresponsive." Apple support docs further explain: "After you switch to a different app, some apps run for a short period of time before they're set to a suspended state. Apps that are in a suspended state aren't actively in use, open, or taking up system resources."
Except Waze... Waze is a battery hog. I always quit that as soon as I'm done with its navigation features.
Your mother was born on a pirate ship
Apps in suspended state very much do use up system resources. Maybe not the CPU, but they'll use up the RAM.
What about apps that are active in the background like Waze?
This is for regular apps. Apps that have background mode enabled can run in background and can consume CPU cycles. They can even use GPS, WiFi, LTE etc. That consumes battery. Most of the running or GPS apps run just fine in background. Otherwise they'd just stop recording once the screen locks or, worse, keep the screen on at all times.
Modern app appers like Apple know that ONLY apps can app apps, NOT LUDDITES who try to force quit apps like it's a LUDDITE computer!
Apps!
This was by far the most common myth about smartphone battery life I heard. The next one is to turn off GPS after use to save battery (as if it changed anything when not using an application using the GPS)
It's kinda funny, actually. The reason the iPhone didn't originally support mutli-tasking is battery life. Now that it does support it, even after going through the extremes they have to keep it lightweight, people still preemptively kill battery hoggish apps.
Apple did try to warn us.
"I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
This only makes one of two things clear... Either Apple people do not use Apple phones, or they are getting kickbacks from ad revenue somewhere.
The battery part is true. I am really impressed with iDevice standby battery life.
But the static image thing.. if that were true that all you are seeing in the task list is basically nothing more than the shortcuts to your recently running apps then that would mean that every time you switch to another app the first app would close. I know this is not the case because app state is preserved when you switch back to the app, even days later.
In addition, sometimes when switching back to an app, it won't function properly. Closing (by flicking up on the task list) and re-opening the app will fix it. So clearly the app's state was screwed up somehow.
Please correct my ignorance, I am not a big Apple user (only have the one work issued iPad).
My eyes reflect the stars and a smile lights up my face.
First off, these gadgets are not telephones, they are computers: Computers you are not permitted to control. Making it impossible to understand anything that is going on, is part of the toy interface designed to prevent you from even attempting to be anything but a pawn, a slave to this Telescreen, this panopticon, this Simon Legree in a pretty, slick case. Why would anyone want such a gadget, much less pay for one? I hate to say it but Stallman was right.
Any app that posts alerts or responds quickly based on location services or provides motion telemetry is pretty much burning battery, however.
Want to save power drain? Only allow location services to apps that need it all the time, and don't allow apps to update tracking on their icons (e.g. mail, texts, etc) unless you really want it.
And set battery to power conservation.
Push all apps you don't actually need to the cloud (delete).
That said, Twitter has no setting to disable internal pics and vids for it's feed so it sucks power big time, especially if location services is turned on, or "see nearby tweets".
-- Tigger warning: This post may contain tiggers! --
I'd be more likely to believe it if one of their devs told me.
All the major smartphone OS vendors keep making this claim. They all assert there is "no reason" to close apps. Some of them were so sure of it they only included capability after enough people demanded it.
They always dredge up the same predictable excuse .. suspend to ram does not use any resources. This is only true of apps that don't explicitly try to do background shit anyway. Given most apps are funded by invading your privacy, wasting CPU time and using your data to exfiltrate information and download ads the suspend to ram theory is rather a pointless one to cling to. It isn't grounded in actual reality.
Audio streaming apps (especially ones that are live streaming like TuneIn, etc.) seem to try and continue buffering the stream after you disconnect bluetooth or unplug the headphones. I don't dislike that feature, but it can really kill your battery if you, say, shut off your car and just grab your phone then go inside a building with little to no cell coverage. That few minutes of the cell radio struggling to maintain the audio stream under poor RF conditions can chew through some battery very quickly.
So yeah, I'll still be killing apps as I see fit. Why an Apple executive would even waste his breath telling people not to force-close apps is beyond me. Too many home buttons failing under warranty?
Everyone is listing off apps that do suck cpu cycles. So apple is wrong about this. So is google. We keep getting these explanation from these vendors which doesnt seem to match real world experiences. Thats because vendors use imaginary scenarios, static apps that dont use resources like gps, cpu or network in the background, which is fine for a game, but reporting apps use cycles.
Google goes even farther and says task killers DECREASE battery life, because the task killer will run often. Total bullshit, but as its easy to test and see the results.
I think think the vendors are using unrealistic use cases, apple and google thinks the average use will just call/text and brows the web, so all other apps are a "rare" thing so its excluded.
Uh, isn't this what the "Background App Refresh" setting is supposed to control? If apps don't run in the background, what is the purpose of this setting and the per-app controls it offers?
Of course it saves battery life if you quit apps that are running in the background!
Quitting things _unequivocally_ makes these devices run better, particularly for video applications. There are far too many occasions where a video will simply not launch until other apps are closed, even 'suspended' ones.
From the summar it appears the reason why closing them doesn't save battery is because they're already shut down entirely,the iOS bar is just lying about it but are, as they call it:
"are actually nothing more than static images intended to represent a list of your most recently used applications. "
YUP yup yup.
I close all apps when I am done. It goes back for decades as correct computer habits. Appls wants your battery to die to sell you a new phone.
Why an Apple executive would even waste his breath telling people not to force-close apps is beyond me.
A user emailed Tim Cook with the question, who forwarded it to Federighi for a response.
#DeleteChrome
In the years of yore, if you buy IBM you wouldn't get fired. It might even got you promoted
No matter how clunky, how useless, how bloated IBM's products were, many people (then) somehow equate IBM to 'excellence'
Same line of thinking is happening with brand names such as Facebook / Tweeter / Google
People can't seem to realize that they are continually duping themselves because of a certain 'brand names'
Muchas Gracias, Señor Edward Snowden !
I get "normal" battery usage out of my iPhone 4S, which is to say maybe a day if I happen to browse the web a bit, Facebook a bit, make a few calls. 2-3 days on very light usage. But on a recent trip to the US, where I had no cell service, my battery life utterly tanked. I could feel it getting hot in my pocket. My guess was that it was constantly searching for a cell signal it could use, and had ramped up the TX power to max to try and get one. When I twigged and turned off the cellphone feature, battery life returned to normal.
This suggests that if you are in a marginal signal area, your battery could be getting hammered because the phone tries harder to maintain a connection.
Oh, that and the usual suspects - the Facebook app is terrible.
AFAIK iOS has a per App option to allow the App to access location always, never, or if the App is running. In the latter case quitting the App saves battery power if it is the only App using location because the phone no longer tries to determine it's location. Now, I could be wrong and this could be new information, maybe the phone always knows it's location and it is only passed to the App if the correct setting is selected. My own experience though is that setting Apps to only use location if running and quitting those apps does save power.
In the meanwhile they enjoy their lunch looking at the 'Fail Harder' poster on the wall that is next to the Zuckerberg portrait.
The reason task killers can decrease battery life on Android is that when an app subscribed to an event and isn't running, it is started. So the task killer may cause the app to be regularly restarted instead of just staying in memory.
Task killers only help with buggy apps that can sometimes go crazy instead of properly getting into standby.
Some task killers are a bit better and can prevent apps from restarting. These can really improve your battery life, in exchange, you usually lose all background features from the app (notifications, sync, ...)
Putting a press release full with absolute correct stuff while at the same time "forgetting" to address the actual issue -- like the programs that do not "run for a short period of time before they're set to a suspended state", but always keep running and therefore are a problem in several ways -- is a time-honored method to throw sand in peoples eyes.
As for the TFA's subject line ? Its a blatant lie-by-omission.
There, fixed it for them.
People double tap on the home button and see this massive list of apps stretching back to the dawn of time and what are they supposed to think?
No-one is going to switch between their current app and one twenty deep in a list like this. It's far quicker to just go and relaunch the app.
I'm not surprised that people think that they need to "kill off" the items on the list. Apple could solve this problem by rethinking the UX - one such solution would be to limit the items on the list and make clear which ones are actually still running in the background vs those which are just a history item.
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Still makes the UI cluttered. If I do it the apple way I have to wade thru a bunch a stuff that hasn't been used in a long while to get to the one I want. Please give us a close all.
Wrong, they are caching junk to speed up loading the most recent apps. True, just like android, the os cycles stuff into the background pretty efficiently, it leaves junk in the cache. The ones in "suspended" mode are indeed using resources, just not enough to actually affect battery life in any noticeable way. The cache, on the otherhand, can get out of hand.
How are they suspended, but not using system resources?
I know for a fact that this is wrong. I have a few exercise apps that I use at night. If I forget to manually shut them down, I find my iPhone is dead or nearly dead when I wake up in the morning.
Also, when I first had my iPhone, I started opening all the apps to see what they do. I had no idea that they were still in the background. After a few days, I wondered why my battery was draining so quickly, to the point that I thought there might be something wrong with my iPhone. Then I discovered how to view and shut down the apps in the background. Every single app I had ever opened was still sitting there open. Oops...
Very much this.
If I don't manually close the Camera app [running in the background] on the iPhone, the phone's battery life decreases by nearly 1/3. And if Safari is running in the background with more than a few javascript-heavy pages open, the battery indicator behaves more like a countdown timer.
Never trust an app to manage itself. Manually shut down anything you don't want running.