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Is this normal? 1 hour of playing.

B

BlackOropher26

iPF Novice
So i've been playing Temple run for 1 hour(straight) and the battery was 53% down to 41% after an hour of playing.
Should i worry about this,or this is normal?
 
noelmcgrath said:
Looks normal, if I were you check to see if any other apps are left open whilst playing. Double tap the home button and if there's and icons showing hold on to one of the icons til it shakes then close them then see if the battery improves a bit.
Click to expand...

That is not needed. Ever. 95% of all apps that run on iOS are suspended the second you leave the application. The remaining 5% have to deal with audio, GPS or some other form of data streaming.

The only time you should use that feature is in when application stops behaving as expected and you want iOS to start over when you launch it.
 
Skull One said:
That is not needed. Ever. 95% of all apps that run on iOS are suspended the second you leave the application. The remaining 5% have to deal with audio, GPS or some other form of data streaming.

The only time you should use that feature is in when application stops behaving as expected and you want iOS to start over when you launch it.
Click to expand...

That's good to know, John!
 
noelmcgrath said:
Well why does my battery drain quicker if I have a load of apps open then?
Click to expand...

It doesn't. You may perceive it does but if you actually did a benchmark test under controlled conditions, you will find it doesn't make a bit of difference. Let me list the things that do make a difference. Especially if you are running iOS 6.

1) GPS. #1 battery killer. And since most GPS is done outside, read the next item.
2) Screen brightness. And Apple changed how screen brightness adjusts under iOS 6 which actually can make the matter worse.
3) Games. The use what are called gaming loops. A constant running piece of code that never goes into a wait state. This allows the developer to always show constant animation. And the more pixels they update the more CPU and GPU power is used.
4) WiFi/Cellular. This battery drainer is variable. The worse the signal, the more battery that is used.
5) Streaming applications. Their impact is based on item 4 and CPU usage to decode the stream.

BTW the real kicker is, by killing the app, it forces iOS to have to reload them from scratch even though the code is still in memory. So by killing you are actually causing iOS to use more battery.

Oh and a side note. The tasks bar doesn't show you which apps are actually loaded in memory. It only shows the last 40 to 80 that you have used. iOS uses an algorithm based on usage pattern to determine what stays in memory and what doesn't. So technically a small app that is in position 35 of the list could still be in memory and you wouldn't know it unless you used an app to show the process list.
 
Skull One said:
It doesn't. You may perceive it does but if you actually did a benchmark test under controlled conditions, you will find it doesn't make a bit of difference. Let me list the things that do make a difference. Especially if you are running iOS 6.

1) GPS. #1 battery killer. And since most GPS is done outside, read the next item.
2) Screen brightness. And Apple changed how screen brightness adjusts under iOS 6 which actually can make the matter worse.
3) Games. The use what are called gaming loops. A constant running piece of code that never goes into a wait state. This allows the developer to always show constant animation. And the more pixels they update the more CPU and GPU power is used.
4) WiFi/Cellular. This battery drainer is variable. The worse the signal, the more battery that is used.
5) Streaming applications. Their impact is based on item 4 and CPU usage to decode the stream.

BTW the real kicker is, by killing the app, it forces iOS to have to reload them from scratch even though the code is still in memory. So by killing you are actually causing iOS to use more battery.

Oh and a side note. The tasks bar doesn't show you which apps are actually loaded in memory. It only shows the last 40 to 80 that you have used. iOS uses an algorithm based on usage pattern to determine what stays in memory and what doesn't. So technically a small app that is in position 35 of the list could still be in memory and you wouldn't know it unless you used an app to show the process list.
Click to expand...

I knew a few things you mentioned but wow! This is a boatload of useful information.

Thanks for posting.

AA

Sent from my iPhone using iPF
 
Really about to hate myself for opening this can of worms. But after considering it for the last 30 minutes, I believe I should mention item number 6 that was left off.

6) Battery age and cycle count.

Now for the explanation to put it in context. Because this one needs it due to the "can of worms" it can cause if not fully understood.

Lithium-Ion batteries have an expected "usage life". This life is usually described in the terms "Number of full cycle charges". IE a Lithium-Ion battery can be rated for 400 cycles. That means you can charge it from 0 to 100% 400 times. Or you can charge it from 50 to 100% 800 times. Or any combo you want to dream up. But here is where it gets interesting. When you have reached 400 full cycles, the battery will only be able to hold 80% of the original capacity when the battery was created in the factory. So lets show the implications in real world terms.

Your iPad is brand new and the battery life begins. You only use your iPad to play one game. The dreaded "Words with Friends". You play that game 100% of the time and never put the iPad to sleep. 10 hours later the battery has gone from 100% to 0% and you put it on the charger till it reaches 100%. You just used up one of your 400 cycles. You have 399 left. You repeat this ritual every single day. And during this time you start to notice something. You aren't getting 10 hours any more. Instead on day 100 of your usage trek you notice you are only getting 9.5 hours. Day 200 you are only getting 9 hours. Day 300 8.5 hours. Day 400 only 8 hours.

You are asking yourself "WHAT THE HECK IS HAPPENING TO MY BATTERY?!?!?!?! They said it would last thru 400 charges!!!!!!!". Remember when I stated earlier that the battery will only have 80% of its potential at the end of 400 charges? That percentage degrades from 100% to 80% over the life of the charging cycles. So at half way, or 200 charges your battery will only be able to hold 90% of the original power you were used to when the battery was new.

So as you use your device on simply a daily basis, if you discharge it once a day, you could see a battery life difference of 25% in just over 3 months.

And that can of worms explains why you could be the most consistent user on the planet but your battery life doesn't stay normal. So it is possible you start to think "It must be something I am doing or running". When in reality it is just chemistry conspiring against us.
 
noelmcgrath said:
Thanks for the info.

Noel
Click to expand...

You are welcome. But please keep this in mind at all times. No one has ever been able to nail down every single battery drain issue with iOS. If Apple released the source code, like Google does with Android, we would have a better idea of what is really going on. At present we only have "profiling" and "debugging" information, from the tools Apple provides us developers, to test with right now. Those tools in both real world logging and under the XCode simulation show that apps, after the home button or standby/sleep button are pressed, are given a bit of time to save off any critical information before they are no longer given any CPU time unless the app registers itself to use the background API calls.

Does that mean iOS is bullet proof and it "always" works this way? I am of the opinion that it is possible for a set of circumstances to arise that break the rules that we think are in place and can cause iOS to go "sideways/unpredictable". The best anecdotal evidence I can provide for that is, everyone that plays with an iOS device long enough learns how to do a hard rest where we press the home button and sleep/standby button at the same time until the white Apple logo appears. If iOS was bullet proof, we would never need that functionality. The fact that Apple built it in says a lot in some respects.
 
Good info, thank you - just wanted to point out that Apple rate the iPad battery as good for 1000 full charge cycles before it will only hold 80%... :)

Before someone panics...;)

Apple - Batteries - iPad

Charge Cycles
A properly maintained iPad battery is designed to retain up to 80% of its original capacity at 1000 full charge and discharge cycles. You may choose to replace your battery when it no longer holds sufficient charge to meet your needs.
Click to expand...
 
Last edited:
janner43 said:
Good info, thank you - just wanted to point out that Apple rate the iPad battery as good for 1000 full charge cycles before it will only hold 80%... :)

Before someone panics...;)

Apple - Batteries - iPad
Click to expand...

Thank you VERY MUCH for posting that link and info. It is good to see Apple publishing that publicly.

So if we redo the math using 1000, that means in 7.5 months you will see your time drop from 10 hours to 9.5 hours. Which is a heck of a lot better than my example :)
 
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