Why does setting up as a new phone improve battery dramatically?

[MoodyM]

I've had an iPhone 4 since day 1. Three times now since I got it my battery life suddenly became so bad I had to restore and set up as a new phone (not restore from backup). All 3 times this has fixed my battery issues.

In all 3 cases my battery life became horrendous (fully charged at 8am, less than half by 1pm, warnings by 5pm). What's more weird is that in all 3 cases it happened suddenly, with no recent install of new apps, etc, that I can recall - one day the battery was pretty decent (for an 18 month old phone with bluetooth and WiFi constantly on), the next day it was horrific.

Although it's a HUGE pain in the ass to restore as new phone (lose all folders, settings, save games, etc), I can live with it; that's not the point of my post here. The point is I'm purely curious as to WHY my battery life very suddenly deteriorates and WHY does restoring as new phone fix it?

Thanks

 

[Applejuiced]

Same here.
My 4S is restored from an old i4 backup.
Used it a little today for some browsing and email, half day 56% left.
My wife's setup as new, used it half day probably more than me for facebook and email 91%
Big difference, when the next update 5.1 comes out Im setting up as new.

 

[MoodyM]

Like I said, it IS a huge PITA, but worth it. I would just love to know WHY it happens.

Another thing I did notice - during the periods my battery was poor, I noticed my iPhone 4 was getting quite hot. Since I restored as new, the battery is fine and the iPhone isn't heating up at all...

 

[Applejuiced]

Like I said, it IS a huge PITA, but worth it. I would just love to know WHY it happens.

Another thing I did notice - during the periods my battery was poor, I noticed my iPhone 4 was getting quite hot. Since I restored as new, the battery is fine and the iPhone isn't heating up at all...

Weird for sure.
I hope once I setup as new the battery life will stay decent.
I dont feel like doing that every few weeks.

 

[MoodyM]

Weird for sure.
I hope once I setup as new the battery life will stay decent.
I dont feel like doing that every few weeks.

To be fair it's only been 3 times in 18 months, but it's still a huge pain to lose all save games, etc.

 

[Calidude]

It's because Apple backs up too much in an effort to make it foolproof for people but this data somehow causes settings to be messed up when restored to a phone.

Apple needs to do a minimal backup instead of assuming their users are brain-dead.

 

[PNutts]

It's because...

Lost me there.

 

[Small White Car]

Lost me there.

What didn't make sense about it?

 

[sbailey4]

Like I said, it IS a huge PITA, but worth it. I would just love to know WHY it happens.

Another thing I did notice - during the periods my battery was poor, I noticed my iPhone 4 was getting quite hot. Since I restored as new, the battery is fine and the iPhone isn't heating up at all...

One thing you guys may want to try is just the settings>general>reset>"Reset all settings" option. Then when it reboots setup as new phone. Run through the wizard bit do not restore from backup. All your apps and data will remain using this method when finished and it does solve the battery issue (well has for a lot of folks). All you have to set back up is any wifi and the email signature few items like that but data and apps are good to go

As to why, well apparently some wifi settings and other settings get hung in some state that keeps them running constantly and resetting the settings unhangs them. At least what I have heard,read somewhere

 

[takeshi74]

Why does setting up as a new phone improve battery dramatically?

Nowhere near enough info to conclude that this is causal rather than coincidental. Setting it up as new is the equivalent of power cycling or formatting and reinstalling. It may help to address the symptom but there could be any of a number of causes.

 

[hel22]

One thing you guys may want to try is just the settings>general>reset>"Reset all settings" option. Then when it reboots setup as new phone. Run through the wizard bit do not restore from backup. All your apps and data will remain using this method when finished and it does solve the battery issue (well has for a lot of folks). All you have to set back up is any wifi and the email signature few items like that but data and apps are good to go

If you set it up as a new iphone, how do all the apps and the rest stay on it??

 

[mms13]

I'm not convinced setting up as new makes it any better. I've gone from an iPhone 3G to an iPhone 4 to an iPhone 4S and have ALWAYS restored from a backup. And while my 4S battery life isn't as good as on the iPhone 4, I'm pretty sure it's on par with most people (about 6-7 hours of usage time).

Like the poster above me said, I don't think it's anything other than coincidence.

 

[Stealthipad]

It has not been proved that it help battery life. I did not set mine up as a new phone and the battery lasts all day and then some.

Do not believe all you read here.

 

[VydorScope]

It has not been proved that it help battery life. I did not set mine up as a new phone and the battery lasts all day and then some.

Do not believe all you read here.

Some subset of the people with the problem claim it fixed/helped their battery problem, so either they are all liars, or it does help some subset of the cases. If it does help some subset of the cases, then its worth a shot since its a safe thing to try.

I do not have a battery problem, so can not speak beyond that.

Why it could work? Some setting that is bugged, a bad install of some app/apps, etc. Plenty of random guessable options for the cause.

 

[wordoflife]

I restored from a backup of my 3GS to my 4S and battery life is okay.

Could be better, but at least I'm not draining in 4 hours.

Lose about 3% overnight (7-8 hours)

 

[tarasis]

Because it stops what might be an errant process. Since 19/12 I have had horrid battery problems with the 4S because the phone doesn't appear to properly go to sleep. Energy diagnostics seem to back this up as they show the phone is Wake mode and logs indicate that a particular process is preventing the system sleeping.

I've seen a similar thing before on the 3GS and the 4 so it def seems OS related. Though I haven't seen the bug in a long old while.