The world's most wanted device is now in the hands of the world's most foremost tinkerers!

The all-new iPhone 4 features upgrades from the 3GS including:

• A redesigned glass & stainless steel body that shaves 3.5 mm off the width and is 3 mm thinner than the 3GS.
• Choice of black or white coloring
• Retina display featuring four times the pixel density of the 3GS
• iOS 4 for multi-tasking
• 5 MP, 720p capturing rear-facing and VGA front-facing cameras

The iPhone 4's design is a dramatic departure from the aluminum and plastic drenched days that have plagued the iPhone in the past.

The rugged stainless steel bezels around the iPhone 4's perimeter double as both structural supports and antennas to boost reception.

• Only time will tell if they absorb shock as poorly as the iPhone 3GS.

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An iPhone first: Interestingly enough, the storage capacity is not etched on the outer case of the iPhone 4.

We'd expect our 32 GB iPhone 4 to fulfill its promise and give us, well, 32 GB. Unfortunately it has an actual capacity of 29.06 GB.

• Given the fact that 301 MB of "other" data is being stored in memory, this leaves the user with 28.77 GB of free space.

In terms of OS, the iPhone 4 comes preinstalled with the newly released iOS 4, build 8A293.

The iPhone 4 is Model A1332. Interestingly, that's a lower number than the A1337 iPad 3G.

Like the iPhone 3G and 3GS, there are two silver Phillips #00 screws at the bottom of the phone. Note: newer iPhone 4 handsets use 5-point "pentalobe" screws instead, requiring the use of a special screwdriver.

In a departure from the design of the 3G and 3GS, removing the screws releases the rear case, not the front glass.

This design makes switching out the rear panel trivial, but unfortunately means that replacing the iPhone 4 front panel will likely be rather challenging.

Removing rear panel gives us a pretty good look at the iPhone 4's innards.

Holy battery! The inside of this thing is dominated by its juice-provider.

It's pretty apparent that real estate was very limited inside the iPhone 4's 115.2 x 58.6 x 9.3 mm footprint.

You can also see pressure contact on the inner face of the rear panel for what appears to be an antenna.

Luckily, the battery can be easily removed once the back panel assembly is out of the way.

The 3.7V 1420 mAh Li-Polymer battery allows for up to 7 hours of talk time on 3G or up to 14 hours on 2G.

The battery connector is different than the one in the 3G and 3GS. Fortunately, the battery is not soldered to the logic board. This will make battery replacement on the iPhone 4 fairly easy to accomplish.

The plastic pull tab for the battery says "Authorized Service Provider Only."

No EMI shield will stand between us and the innards of this iPhone 4!

The EMI shield comes off after five screws are removed to reveal lots of important connectors.

Upon further inspection, it looks like the EMI shield actually acts as the Wi-Fi antenna. The long screw at the top and center grounds the antenna.

The logic board is heavily embedded under wires and EMI shields.

While we're not too busy, let's talk RAM. Unlike the iPhone 3GS and iPad, which are both equipped with 256 MB, the iPhone 4 has a whopping 512 MB!

The increase in RAM allows for a larger amount of cached data allowing for a smoother and faster user experience.