Looks like it has been a long time since we talked about the battery issue with the recent iOS updates on iPod Touch. Back in September this year, we had written about an issue experienced by many iPod Touch users who had upgraded their device to the then latest iOS update.
The common complaint was that updating the iPod Touch to iOS 4.0 resulted in an overnight drop in the average battery life of the iPod. We had also suggested a temporary fix to the issue back then.
Now with Apple having released iOS 4.2.1, one may have assumed that such issues may have become a thing of the past. However, it looks like the battery drain issue continues to affect a significant number of iPod Touch users.
One common observation is that the Wi-Fi on the affected phones do not seem to be deactivated when the phone goes to sleep. Normally, the iPod Touch would only reconnect to Wi-Fi everytime it is “woken up“. But the Wi-Fi on the affected phones continue to stay active even when the device is in idle mode thereby draining battery life. The root cause for this could be an application – native or third party. But that is yet to be ascertained.
Have you been able to decipher it on your end? Let us know in the comments or join other folks in the deliberation on the Apple support forum here.