As Gizmodo puts it, Apple has officially re-revealed the next generation iPhone – dubbed the iPhone 4 at the launching keynote of WWDC 10. While we had seen it a lot of times before thanks to all the leaked pictures over then internet, its good to finally see the device officially and know about its features. And speaking of which, according to Steve Jobs, there are over 100 new features in iPhone 4, the biggest of which he demoed on stage.

Of course, some features were truly innovative, while some ideas were borrowed from the industry and polished to perfection. Here is my breakdown of what I think is most exciting about the iPhone 4.

The Name

The first thing that struck me about the iPhone 4 is the name. Its nothing fancy or complicated or something which has tons of different brands in it (like HTC Google Nexus One or HTC Sprint EVO 4G). Its simple yet descriptive and clearly gives the idea that we are talking about the fourth generation device.

The Design

A lot of people might be unhappy with Apple for dropping the curves and tapered back but I totally agree with them. The old design was – well old to say the least. It had been around for too long now and it was time for a change.  The new design stands at a stunning 9.3 mm making it the slimmest smartphone out in the market right now.

The Engineering

While it may be an aspect of the overall design, the innovative engineering of the iPhone 4 does deserve credit. The best part – the stainless steel band which also dubs as the antennae for Wi-Fi and 3G radios. As for the front and back, they are made of highly durable and scratch resistant glass which according to Apple is “same as the glass used in the windshields of helicopters and high-speed trains. Chemically strengthened to be 20 times stiffer and 30 times harder than plastic”.

The Display

Dubbed Retina Display, the new 960 x 640 pixel display is simple stunning. The pixel density is actually higher than the human eye can resolve. Some might argue that it is an overkill for the 3.5″ display but I think it would be perfect. Its also an IPS panel with a good contrast ratio of 800:1, and before you even wonder, lag doesn’t matter on a mobile device so no problems there as well.

The A4 Chip

After the iPad, the Apple designed A4 chip also finds its way on the iPhone. If the chip is similarly spec’d, then expect a superior experience to any other device in the market right now until 1.5 GHz Snapdragon or its dual-core variant rolls out.

Surprisingly, there is no word on the about the RAM here, but I’m guessing its 256MB, same as the iPhone 3GS. Though it would help if its actually more (like 512MB) since iOS 4.0 can now Multitask as well, which brings me to…

The Multitasking

Okay its not true multitasking like on the desktop or other mobile operating systems like Symbian or WebOS, but it is definitely more efficient than those two, and in many ways is a lot similar to what you can do in Windows Phone OS 7 (speaking of which, Microsoft should also be simplifying the name).

The Camera

The bump to a mere 5 mega pixels might not sound much, but Apple says it believes in the whole packaged experience when it talks about photos and videos. This include editing the content on the device, which would now include iMovie. To top that off, the iPhone 4 would also record videos in 720p HD at 30 frames per second, along with an LED flash.

The secondary camera on front can be used to make video calls of Wi-Fi, something they are calling FaceTime. Apple may sound like they have invented something totally new here, but video calls have been around on other phones since the early in the past decade.

The Gyro

The last feature I would like to highlight is the Gyro, which joins the sensory arsenal of the iPhone, which includes the accelerometer, digital compass, A-GPS , Proximity, and ambient light sensor. The three axis gyroscope brings a whole new degree of motion sensing experience to the iPhone. Think of it like a Wiimote with Wii MotionPlus attached, only that it also has a multitouch display.

That’s about all my favorite picks from the new iPhone. Of course it doesn’t mean that’s the only thing new there. You have a lot of new features in iOS 4.0 as well, along with new apps like iBooks with PDF support, a unified inbox with threading, and an overall improved battery life thanks to a larger battery.

iPhone 4 is available in two models with two colors each. The 16 GB model would run for $199 while the 32 GB model would cost $299 on contract from AT&T. The iPhone 3GS 8GB is now selling for $99. The iPhone 4 would be available June 24, but you can pre order yours starting June 15.