Do I really need a new iPhone?Confused in California writes: So, I have an iPhone…maybe 3G? It’s white, I can tell you that much. It also doesn’t do that two-way picture thing, if that is helpful.

Certain people (who shall remain nameless) badger me incessantly to get a new iPhone, but this one works—makes calls, takes email, makes texts (albeit usually indecipherable). All this, despite an unfortunate toilet-surfing accident.

Do I really NEED a new phone? Why, except to say it works a little faster (and does the two-way photo thing)?

Dear Confused in California: It sounds like you have either the iPhone 3G or the 3GS, meaning your phone is at least two years old and about to slip yet another generation behind, what with the imminent arrival of the rumored iPhone 5.

OK, so do you really need a new iPhone? Of course not. If you’re comfortable with your 3G (or 3GS), you’ve figured out how to use it, and it’s worked its way into your daily life, then by all means, hang onto it—particularly if you couldn’t care less about three-axis gyroscopes, HD video recording, or the two-way photo thing (a.k.a FaceTime video chat, which I’m not that excited about either).

But here’s the thing: you may change your mind once you feast your eyes on the iPhone 4. Why? Two things: faster performance, and the glorious Retina Display.

The engine that powers the iPhone 4—Apple’s A4 processor—makes for peppier overall performance, not to mention better battery life. Ever feel like your old iPhone is sputtering while you’re trying to surf or searching for a phone number? If so, the iPhone 4 will feel smooth as silk, and the next-generation iPhone promises to be faster still.

OK, so what about the Retina Display? Well, one word: gorgeous. Apple managed to cram in 326 pixels per inch into the iPhone 4’s razor sharp display—a resolution so tight that the text and images on the iPhone’s screen look like they’ve been painted onto the glass. Glance back at the older iPhone’s display, and it’ll look like you’re peering through a screen door.

Nice, and maybe tempting. But here’s one thing your iPhone 3G/3GS has over the iPhone 4: it’s tougher. The glass screen is a weak point, of course, but at least the back is made of plastic—and indeed, I’m sure the back of your iPhone is riddled with little nicks and scratches from the occasional tumble. But it’s still more or less intact, right? (And it sounds like your iPhone even survived a dunk in the toilet.)

Both the front and back of the iPhone 4, however, are made of glass—drop it the wrong way, and your new iPhone could wind up with a spiderweb of cracks on its back panel (all the more reason to invest in a case). Whether the upcoming iPhone 5 will arrive with a new, tougher design remains to be seen.

Bottom line? Nope, you don’t need to give up your old iPhone; if it’s working for you and you love it, keep it. But don’t be surprised if you think twice after taking the speedier, eye-popping iPhone 4 for a test drive.

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