What do you do when Apple ships a new device two days early to one of your friends? If you're iFixit, you persuade them to let you strip it down into pieces and parts. iFixit's in-depth teardown doesn't hold many big surprises after an early prototype leaked to the Web, but it did reveal several fascinating details.

The two screws at the bottom of the device release the back panel of the iPhone 4; on previous models, these released the front display assembly. The bad news is that this makes replacing the display a little more challenging, and the display and touch panel are all glued to the front glass, so it's a total module replacement if the glass does break. The good news is that it's very easy to get to the "huge" Li-ion battery inside. It's also not soldered to the logic board, so it's relatively easy to replace despite an "Authorized Service Provider Only" warning.

iFixit describes Apple's engineering of the wireless antennas into the stainless steel frame and bezel of the phone as a "work of genius." The antenna design should improve reception, especially for those on the edges of coverage areas. Furthermore, Apple has reportedly fine-tuned how the iPhone chooses an open channel. It will "utilize whichever network band is less congested or has the least interference for the best signal quality, regardless of the actual signal strength." According to iFixit, it should improve reliability on AT&T's network.

Behold, the Lilliputian logic board of the iPhone 4.

We already know that the iPhone 4 is powered by the Apple A4 processor, just like the iPad, and iFixit confirms that it has 512MB of RAM compared to the iPad's 256MB. As we noted previously, this should improve performance for multitasking, caching webpages, and running apps with high-resolution graphics. iFixit contends that the A4 processor is running at 1GHz, like the iPad, though some early benchmarks suggest that it might actually be running slower—more like 800MHz. The benchmarks aren't conclusive, though; until there is a reliable benchmark that can run on all three devices, the jury is still out on this one.

iFixit also identified the major suppliers for the chips on the iPhone 4 logic board, including: Skyworks cell radios, Broadcom WLAN and GPS, STMicro accelerometer and gyroscope (iFixit says Apple is the first to have access to STMicro's gyroscope chip), a TRiQuint GSM chip, Samsung flash memory, Apple-branded Cirrus Logic audio codec, TI touchscreen controller, and Numonyx RAM. Many of these parts are similar to those used in the iPad or previous iPhones, so no major surprises here.

One last intriguing detail is that Apple is using an aluminum-based ceramic glass for the front cover (and believed to be used for the back cover as well). Identified as Corning Gorilla Glass, it is considered ideal for touchscreen devices because of its strength, light weight, and resistance to scratching or damage. iFixit notes that the material is supposedly 20 times stiffer and 30 times stronger than polycarbonates (material data sheet).

Listing image by iFixit