iPhone 4: seven good reasons to upgrade, three to give pause

iPhone 4 is here, and tens of millions of current iPhone users have to make the decision whether or not to plunk down a couple hundred bucks to make the upgrade. Here are several good reasons why you should go ahead and take the plunge, and at the end of the list, a few reasons to give you pause:

1. It’s faster: the iPhone’s ever more sophisticated apps demand more processing horsepower to go with it, and iPhone 4 uses the same A4 processor technology as Apple’s iPad, which is bound to give you back a few nanoseconds here and there.

2. Better battery life: seeing how much thinner iPhone 4 is than its predecessors, it seems like they could have crammed a whole lot more extra battery life in there if they’d wanted to. But as it is, the new iPhone has what Apple claims is up to 40% more battery life, and while a look at the specific breakdowns by usage type suggests that the estimate is high for the features you’re likely to use most, the bottom line is that iPhone 4 has a noticeably longer batter than iPhone 3GS, iPhone 3G, or the original iPhone.

3. iOS 4: Apple’s new mobile operating system (previously known as iPhone OS 4) will also be available for older iPhone models, but some of its key features will only be able to fully fun on the faster more powerful iPhone 4. Just because you upgrade your existing iPhone to iOS 4 when it’s released doesn’t mean you’ll be getting the same iPhone 4 experience on your existing iPhone.

4. iMovie: If you’re of the opinion that no mobile video should ever be shown to anyone until it’s benefited from some basic editing, the iMovie app means you’ll no longer have to wait until you get home and sync your mobile video to your computer before being able to clean up the loose ends. We’re still waiting to officially hear whether iMovie will run on the iPhone 3GS. But even if it does, iPhone 4 has a much higher quality video camera (HD in fact) than the 3GS does.

5. FaceTime: Yes, it’s seemingly a gimmick to begin with. And yes, its wifi-only status means you’ll more or less have to schedule video calls ahead of time on both ends to make sure you just happen to be within range of wifi when the phone rings. But tell us you’re not at least a little bit tempted to use it to communicate with a loved one.

6. Upgrade pricing: Many iPhone 3G users skipped the iPhone 3GS because they weren’t eligible to buy it for the advertised price and found themselves being asked to pay two to four hundred dollars above sticker. And while a fair number of users will fall into that trap again with iPhone 4, the number will be significantly lower this time around. AT&T, who finally did something customer-friendly after three years of being the bane of most iPhone users’ existence, has said that anyone who was going to be eligible to buy the iPhone 4 at the advertised price by the end of 2010 will instead be able to do so from day one. What does that mean for you? AT&T has a secret formula for whether you become eligible either twelve or eighteen months after you bought your last iPhone, and rather than trying to do the math, it’s better to just confirm it on wireless.att.com – but the bottom line is that many iPhone users who bought their current iPhone prior to 2010, and nearly all iPhone users who bought theirs prior to mid 2009, will be able to get their hands on iPhone 4 for the actual $199/$299 pricing.

7. New antenna technology: Speaking of AT&T, despite its obvious deficiencies, carrier signal alone isn’t the only factor in call quality. AT&T customers who’ve moved from a RAZR to an iPhone are aware that AT&T’s call quality can magically jump by leaps and bounds simply by moving to hardware with better antenna technology. It’s not yet clear whether the new antenna technology in iPhone 4, which uses the device’s frame as an antenna, is supposed to result in better reception or merely allowed Apple to stop wasting space on a separate antenna – but we’re eager to find out.

And as promised, here are three reasons for current iPhone users to think twice about upgrading to iPhone 4…

1. Capacity: iPhone 4 has room for a gyroscope but not for anything more than thirty-two gigabytes of storage space? Even the iPod touch, which is nothing more than a fake iPhone, has a sixty-four gigabyte option.

2. Practicality: The bulk of the iPhone’s new features, whether it be mobile video, or FaceTime, or the newly built in gyroscope, are niches and not for everyone. The increased specs, from battery life to speed, are incremental and not game changing. If none of the new features and enhancements matter to you, is it worth upgrading just so you can say you’re using the latest and greatest?

3. Contract: If AT&T tells you that you’re one of the unlucky current iPhone users who has to pay four or five hundred dollars or more for an iPhone 4 because you’re not yet eligible for it, then whether it’s worth its price tag becomes a whole different equation.

In any case, if you missed iPhone 4′s full rundown of new specs, you can find it right here.