Has iOS 5.1 squashed the iPhone battery bug?

Has iOS 5.1 squashed the iPhone battery bug?

Summary: Right now, things look promising.


Question from today's mailbox:

You've talked a lot about the battery bug that iOS 5 introduced (and that iOS 5.0.1 failed to fix) to the iPhone 3GS, 4 and 4S. Do you think that iOS 5.1 finally fixes this battery drain bug?

Well, it's early days really, given that I've only had iOS 5.1 on my iPhone for a few hours. However, given that I noticed the initial battery bug within hours of installing iOS 5, and then I quickly realized that iOS 5.0.1 didn't fix the problem a few hours after installing it. You don't need to spend a long time with iOS updates to have a pretty good idea of how they affect battery life.

Normally my iPhone 4 has been discharging around 15 - 20 percentage points off its battery life overnight on both iOS 5 and iOS 5.0.1. This has been a consistent and repeatable pattern for week now.

Last night I noticed something different. Overnight battery discharge was only 6 percent. That's not just an improvement, it's a significant improvement. This leads me to believe that this update does indeed squash whatever battery bugs were in iOS 5/5.0.1 (at least the battery bugs that were affecting my handset).

I'm also noticing my handset drain at a much slower rate when it's out of the dock and when I'm using it. Simple actions such as downloading email could knock a percentage point off the battery, which was behavior I didn't see prior to iOS 5, and it is behavior I'm not seeing with iOS 5.1 now.

Right now, things look promising.


Topics: iPhone, Apple, Hardware, Mobile OS, Mobility, Operating Systems

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  • iPhone 4S battery

    I have noticed my iPhone 4S battery life is already significantly improved. Off the dock and in continuous use since 6:00am (its now 7:05am), I have used Foursquare, facebook, email, and taken 3 pictures and it's still at 100%. Prior to this it would have definitely already been down 2 or 3 percentage points.
  • 5.0.1 was a dud

    Anyone who thinks that a major bug like one that would drain a battery can be fixed in a few weeks has no idea how well done computing engineering works. These things take a long time to figure out, fix and then test, especially issues that are not instantaneous (like battery draining over time).

    We've entered an age of computer engineering when programs are not thoroughly tested when they come out and are quickly fixed on the go. That is the wrong way of doing things.
    • Business as usual

      The tension between perfection and shipping has always been the norm. When talking about millions of lines of code bugs are always there.
    • One thing I disagree with...

      "We've entered an age of computer engineering when programs are not thoroughly tested when they come out and are quickly fixed on the go. That is the wrong way of doing things."

      Not so. At least in my shop, and those I know in other shops in my area...we're doing more and better testing than ever. Code coverage tools are becoming prevalent, and it is now common to require 100% coverage by unit tests, given that mocking frameworks make it much more easily possible than otherwise. As a result, we're catching many more regressions than ever before and turning out higher-quality products from the get-go!
    • Bill Gates Would Still be Poor

      If Microsoft waited to ship Windows, until all the bugs were gone, back in the early 90's, Bill Gates would be unknown and living on the street, and we would still be running DOS on our PCs. It's a matter of economics. Most engineers struggle with this. They won't things to be perfect before ship, but business leaders need to generate revenue to keep the engineer;\'s paycheck coming.
  • Unrelated iOS 5.1 Question

    Anyone upgrade their iPhone 4S to iOS 5.1 and notice it now says 4G instead of 3G when on the Cell network?
    • 4G signal increased via AT&T network and iOS 5.1 update

      My AT&T iPhone 4S now says... "4G" in the top left!@
      oh yeah!
      5.17 Mbps download just now, scratch that, I just reached 8.5 Mbps download and 6 upload via AT&T 4G speeds in Provo, Utah.
      • It's an error

        Google it. AT&T changed the labelling that appears on your phone, but it's still a 3G phone.
      • RE: It's an error

        Actually it is because the iPhone 4S uses HSDPA+ which other companies already call 4G because of it's speed enhancements. If you connect to an area that does NOT have HSDPA+ the phone will say 3G.

        Still kind of misleading though but apparently the term 4G is about the speed capabilities which are faster than the iPhone 4/3GS using the standard HSDPA.
  • Glad they fixed the battery but...

    how about fixing the gaping security hole now about being able to get access to a phones contact list and dialer while the phone is locked with a passcode.
    • I don't have an iPhone

      Have you confirmed this? Is so, gaping is not the proper adjective.
    • I'm Not Normally An Apple Defender But...

      The security holes in question require physical access to the device and a rather complex series of hacks that seem to require more luck than skill. I don't think they are a very high priority. The most expedient route for a wanna be hacker to try would be to simply crack the pass code, or do a wipe of the phone by connecting it to iTunes.
      Doctor Demento
  • On my iPad 1

    The battery life seems to be not quite as good, however, the iPad has come back to life. After the update to 5.0 and 5.01 its operation become jerky and slow in many Apps, especially Safari and the App Store, Appa also crashed a lot. Now it is lively, fast and a lot more fluid; a pleasure to use once more. Now I can hold out a little longer before buying the new iPad...or can I?
    A Grain of Salt
    • I noticed the same thing.

      However I thought my particular machine was simply broken after the couple drops I laid on it. Glad to be wrong.
  • iPad

    I have rev 1 of the iPad. Installed 5.1 and used it as I normally would. I woke up this morning with about 20% more battery capacity than I normally have by that time. Seems whatever they did helped my iPad and I wasn't unhappy with it to begin with.
  • I Never Noticed a Battery Problem......

    Granted, I have a 4th generation iPod Touch and NOT an iPhone, maybe that makes a difference (even though the only hardware difference between a 4th generation iPod Touch and the iPhone 4 is the lack of a cellular radio)
    Doctor Demento
  • How 'Bout That!

    Sure enough, my 64GB 4S battery life is improved under 5.1. After eight hours of fairly light use (email, weather, two phone calls, etc.), I'm at 82%. Normally I would be much closer to 60%. So they plugged the leak.

    Or maybe they just recalibrated the percentage...
  • Battery Drain Issue

    Yeah ... I really think the issue has been fixed. The battery life of my 4S has been considerably better today. I've been down under 40% by this time of most days and today it's at 77%. Significantly better.

    -Max :D
    Max Peck