We're not going to beat around the bush -- in our approximation, the iPhone 4 is the best smartphone on the market right now. The combination of gorgeous new hardware, that amazing display, upgraded cameras, and major improvements to the operating system make this an extremely formidable package.

Pro. FaceTime video calling. Handsome thin design. Better battery life. High-definition video recording. Supersharp display. Multitasking, folders and other enhancements through iOS 4. Generally good voice quality. Con. Battery can't be removed. Memory can't be expanded. No support for Adobe Flash video sites. For FaceTime to work, both parties need to be using the new iPhone and have Wi-Fi access. Occasional dropped calls.

The iPhone 4 is a dramatic redesign. It manages to pack a radically sharper screen; a second, front-facing camera; a larger battery; a better rear camera with flash; and a faster processor into a body that is 24% thinner, a bit narrower, and retains the same length and weight as its predecessor’s. In fact, Apple claims that the iPhone 4 is the world’s thinnest smartphone and sports the world’s highest-resolution smartphone screen.

The fourth incarnation of Apple's iPhone is an incrementally improved, familiar device—not a new kind of device, as was the case with the recent introduction of iPad. Yes, the notable features with iPhone 4—both the device and the iOS4, which came out yesterday in advance of the iPhone itself—are mostly tweaks. But what tweaks they are: Apple's focus on improvement is as much key to the quality of its products as innovation. Still, there's one flaw it can't completely eliminate: the unreliable quality of calls placed over AT&T, which remains the iPhone's only U.S. carrier.

With iPhone 4, Apple again shows that it's a powerful player in the smartphone wars. It won't be for everyone, and AT&T remains a sticking point, but the handset's striking design, loaded feature set, and satisfying performance make it the best iPhone yet.