iPhone 4

Even from the outside, you’ll see that the iPhone 4 marks the biggest upgrade since the iPhone 3G (the 3GS didn’t add much beyond a compass). The profile is thinner and you’ll notice a new front-facing camera (more on that later). The iPhone 4 also serves as the debut device for the newly named iOS 4 operating system, which brings such much-needed features as multitasking, a unified e-mail in-box, and app folders for the home screen.

On the whole, this iPhone 4 has us more excited than we were last year when the the 3GS was born. The new features, particularly those in the new operating system, are long overdue and we welcome any efforts to improve call quality (remember that it is a phone, after all). There were a few things that we were hoping for that we didn’t get–a 64GB model, among them–but we look forward to reviewing this model.

The new iPhone’s design is a sharp departure from the previous iPhone models. The front and back sides are glass, both surfaces are flat, and a stainless steel border circles the entire phone. Indeed, it looks very much like the photos that appeared on Gizmodo after an Apple engineer allegedly lost it in a Redwood City, Calif., bar back in April. Other new design elements include the aforementioned front-facing camera, split volume controls, a noise-cancellation microphone, and a new LED flash with the main camera lens. The iPhone 4 also switches to a Micro-SIM format, just like the iPad.

We welcome the new design elements on a couple of levels. The flat backside means that the iPhone will no longer wobble when it’s resting on a table. Also, even though the overall effect is a tad boxy, the handset has a clean and unmistakeably Apple look. At 0.37 inch (9.3mm), the iPhone 4 also is 25 percent thinner than its predecessors. Jobs called it the thinnest smartphone around, but since that race changes daily, it may not hold the title for long.

We haven’t had an opportunity to test noise-cancellation feature, though we expect that they can only do good. The camera flash also is a win, and we’re hoping that the front-facing camera can be used for self-portraits in addition to the new FaceTime feature. The split volume buttons are fine, even though we never had a problem with the previous control.

That said, we have a couple of concerns with the new design. It’s clear that Apple is pushing the Micro-SIM format, though we’re not exactly sure why. On a superficial level, it saves plastic, but a Micro-SIM doesn’t offer any functional benefits over the standard SIM. Is Apple starting a new format war or is this merely a barrier (albeit, not a very high one) to iPhone jailbreakers? We’ll have to wait and see the answer, but in the meantime we hope that you’ll be able to use the same Micro-SIM between on an iPhone 4 and an iPad 3G.

We also have a small concern about all that glass. It is shiny and beautiful, but the glass attracts smudges by the ton and durability remains a concern. Jobs said that glass better resists scratches, but we hope that the iPhone 4 will take a few drops to the floor without cracking. On the upside, it feels solid in the hand.

The stainless steel border is more than just decorative; it doubles as a new antenna that circles the entire phone. Though Jobs did not promise that it would improve call quality or Wi-Fi reception, its very mention is an indirect admission (and the first that we’ve seen by Apple) that data and voice reception has been troublesome and needs to be addressed. Though current iPhone users largely blame AT&T for connectivity problems, remember that both a carrier’s network and a phone’s antenna play a part in reception.

Whatever the reason for its development, the redesigned antenna should be good news for iPhone users. And if it improves call quality while looking good at the same time, that’s even better. We’ll have to wait and see.

Apple has a unique talent for making us want something we never knew we wanted. The iPhone 4 features a 940×640-pixel (or 300 326 pixels per square inch) “Retina Display,” which is four times the resolution of previous iPhone models. What’s more, it uses the same IPS display that’s found on the iPad with an 800:1 contrast ratio. Though we’ve always thought highly of the current iPhone displays, Apple rarely rests on its laurels. Also, the company needs to compete with the gorgeous AMOLED screens and TFT displays we’ve seen on many Android phones like the HTC Evo 4G.

In our brief hands-on, the display is clearer than crystal clear (Brian Tong’s words). Since it renders all text the same, we had no problems reading a variety of Web pages. Photos looked especially lovely, particularly when you compare the same image between an iPhone 4G and an iPhone 3GS. We’re not inclined to believe all of Apple’s claims about the display’s capabilities, but there’s no denying that it looks good.

Processor and battery life
Just as we thought, the iPhone 4 will feature the same A4 chip that’s found in the iPad. The result is a faster processor (always nice), plus improved battery life (even better) given the A4’s efficient power management. Add in a bigger battery and we get a promise of 7 hours of talk time now, 6 hours of 3G browsing, 10 hours of Wi-Fi browsing, and 300 hours of standby. Bravo on all counts if those times hold up.

Camera changes
The iPhone’s camera has always been decent, but it’s lacked features found on many basic phones. That’s why we applaud the 5-megapixel resolution, the new LED flash, and the 5x digital zoom. The iPhone 4 also has a new back-side illuminated sensor, which requires a more-detailed explanation. Check out my colleague Stephen Shankland’s blog for a detailed look at the technology.

Though the new handset isn’t called the “iPhone HD” (one of its rumored names), it records 720p high-definition video at a constant 30 frames per second. The demo looks great, even if the iPhone isn’t the first cell phone to offer this capability. We can’t wait to try it.