Like most iPhone users out there, I'm always excited about firmware upgrades because you EXPECT things to be BETTER afterward, right? I just so happened to be up late, writing, on the night that the 2.2 firmware update hit, and wasted no time in downloading it to my precious iPhone 3G. Once completed, everything was fine and much improved!  Or...   was it?

It wasn't long until I realized that my iPhone was heating up excessively and I couldn't keep it close enough to a charger. If my phone was topped off when I went to bed, and left unplugged, it was dead by morning. How could this be? Even a reset didn't help. There had to be some app running in the background that was chewing up my battery faster than Pac-man on a steroid/speed cocktail. Are YOU having the same problem since the 2.2 update? If so, read on. This tip may apply to you!

Does this picture look familiar? It's what I was looking at after only mere hours off the charger. The only thing I could think of was that an app was running in the background, draining my battery even when my iPhone was only in standby and unused.

I closed any apps that could be the culprit - I logged off of my IM app. Since the 2.2 update, I had changed nothing, so I assumed the update made some kind of change that resulted in something on my iPhone being 'always on' and, likely, using data at a voracious rate. I reset my Safari to make sure it wasn't the culprit. What could it be?

The only other app on my phone to use data was Mail. I have Exchange set up on my iPhone so that I can get my company mail, contacts, and appointments in as close to 'real-time' as possible. Could the update somehow have affected my Exchange settings and made everything wonky? It was time to experiment.

One thing I've learned through painful experience is that, in most cases, a problem can be fixed by starting with the simple things. I've learned this when diagnosing car problems. If the car doesn't start, why? Does it turn over when you turn the ignition? Nothing at all? Could be the alternator, right? Oh wait! What about the battery? It's a lot cheaper to check the battery and replace it before digging under the hood and replacing an alternator.

With this start-with-simple approach, I deleted my Exchange email account and then set it up again from scratch. Guess what? It worked. For some reason, the update did not play nice with existing Exchange settings and email. Once the update ran, my Exchange was locked into a constant 'on' state and was endlessly searching for mail that wasn't there, rather than waiting for the mail to be 'pushed'. No wonder my iPhone was like carrying a hot coal in my pocket! A simple deletion and setup of my Exchange mail account resolved the problem and my battery life has been normal ever since.

If you use Exchange on your iPhone, I recommend deleting and reinstalling your mail account after all future iPhone updates. Then, you'll avoid the distress I went through when I couldn't get 5 hours out of my iPhone after a full charge.