The fix is on? iPhone 2.1 software out tomorrow.

One of the key elements of Apple chief executive Steve Jobs’ keynote during this week’s “Let’s Rock” event was not a product announcement at all, but an announced update. The iPhone 2.1 software update is due out tomorrow, and Jobs has set expectations extremely high for it.

“The 2.1 software update is a big update. It fixes lots of bugs. You’ll get fewer call drops. You will get significantly improved battery life for most customers. We have fixed a lot of bugs where if you have a lot of apps on the phone, you’re not going to get some of the crashes and other things that we’ve seen. Backing up to iTunes is dramatically faster,” Jobs stated during the keynote.

Application bugs. Dropped calls. Battery life. Backing up. Perhaps the four most-complained-about elements of the iPhone — and Jobs is claiming that this update will fix them all.

Of course we’ve heard it before. First the 2.0.1 update was going to fix problems, then the 2.0.2 was supposed to solve all the issues. Apple and AT&T were so sure that 2.0.2 was going to fix the connection issues that some users were having, that it went so far as to send text messages to every iPhone 3G owner telling them to download the update. Still, many felt problems persisted.

But there are indications that this update could be the one. The 2.1 software is actually already out for the iPod touch and while obviously that device doesn’t have connection issues (because it’s not a phone), talk is circulating that elements of the applications have improved dramatically. Specifically, application updates done on the phone are said to increase fivefold, an AppleInsider forum member noted. It’s also worth noting that when you update an application on the phone its icon retains its position. (Right now when you update an app on the phone it moves to the end of the last screen.)

The one part of Jobs’ comments that worries me is the “for most customers” part that was added on to his claim of better battery life. Perhaps he’s just covering his bases. As I’ve argued, some complaints about battery life have to be tied to the fact that customers use the iPhone so much, for many different functions. So maybe Jobs just wants to make it clear that for extreme users of the device, the battery life will never be great.

The 2.1 update will launch at some point tomorrow and will be a free upgrade for current iPhone owners.