At first I thought I was alone, and that my iPhone 3GS was defective, but now it looks like battery complaints relating to iPhone OS 3.1 are far from isolated incidents. Apple is officially investigating the matter, according to The iPhone Blog, which is something the company generally only does if enough people crow loud and long enough.
My own experience is that the iPhone charges in far less time than it normally would, and then only lasts about 12 hours on standby with my average daily usage of around three hours talk/browsing/gaming time. That’s probably a full 12 hours of standby off of what it used to be able to handle post-updating.
The behavior seems to indicate that the iPhone isn’t recognizing or using the full capacity of the battery anymore. I’ve tried resetting the phone, but I haven’t done a full restore, since I’d rather wait and see what kind of fix Apple comes up with before I lose all my data and settings. Also, support forum posters indicate that doesn’t correct the problem.
Other problems include a sticky battery indicator, which sometimes also won’t go below 100 percent after a full charge, and a huge additional drain when using Push features. My temporary fixes include turning off Push altogether, and charging the phone whenever I’m near an accessible power outlet, since the battery indicator can no longer be trusted.
Hopefully, Apple can solve this quickly with a x.x.1 release, but until then, drop by the support forums and answer the questions Apple is asking about the problems to help expedite the process. You might even be able to get one of the “Battery Life Logging” profiles Apple is distributing to gauge the extent of the problems. If you’re experiencing similar issues, please share in the comments with specific details.