The recent iOS 5 firmware update isn’t the first to see reports of unusually high battery drain after installation, as iOS 4 and various point revisions also caused problems for some users.  But the reduced battery life seen with iOS 5 is something that was reported during the beta testing, and was cured on at least one occasion, so it’s surprising to see it return in the final release.

For me, the decreased standby time was immediately noticeable, with between 30% and 50% loss overnight.  Interestingly, I was abroad when iOS 5 was released and had not only disabled location services, but cellular data too – and was therefore expecting to see a general improvement in battery life!

Since returning and for the first time ever, my iPhone 4 battery completely drained overnight, to the point where it displayed the empty battery image and a request to plug it into the charger.  I’ve switched off iCloud syncing to see if that made a difference, which it seemed to, but not enough to say it was the sole cause of iOS 5′s heavy power consumption.

I’m not the only one who has experienced these problems either, and a Google search for iOS 5 and battery sees the word ‘drain’ automatically added in second place.  PC Pro noted similar problems on one of their test devices, the Apple support forum has several threads related to the issue, and GDGT’s Ryan Block tweeted that he was experiencing the same problem on an iPad 2.

So what’s the solution?  Well, aside from waiting for an official fix in a future version of iOS, there are several workarounds you can try right now.  Here are the most popular:

• Delete your email accounts on the phone, then set them up again.  There is some speculation than old account settings don’t agree with iOS 5.
• Remove the weather and stocks widgets from the new Notification Center.
• Check under Settings/Notifications to see what’s enabled, as there have been reports of previously disabled apps becoming active after upgrading.  Turn off anything non-essential.
• Ensure Bluetooth is switched off when you aren’t using it.
• Check under Settings/Location Services/System Services and uncheck anything non-essential, for example Traffic or Setting Time Zone options.
• You could also try resetting your phone’s Network Settings under Settings/General/Reset/Reset Network Settings, just be aware than when you do this you’ll lose all your stored Wi-Fi passwords; so make a note before you do!

These are the most common tips floating around at the moment, but if you’ve used another technique and improved your iOS 5 device’s battery life, then let us know how you did it in the comments.