TUAW blogger TJ Louma enquired AT&T regarding the upgrade plans to iPhone 4 and he found out that if you’re lucky enough to qualify for one of the early upgrades that get you out of usual 18-months AT&T commitment period, then you pay just $199 for 16GB and $299 for 32GB.

If your upgrade date is January 1, 2011 or after, early pricing for the iPhone 4 will be US $399 for the 16GB model of $499 for 32GB model.

If you plan to upgrade it to “no-commitment” contact, meaning that there’s no early termination fee for dropping the phone led two years, the price sneaks up another $200 to $599 for the 16GB model and $699 for the 32GB unit.

As with major purchase you should consider these pricing factors before you jump into purchasing a new iPhone. Remember, there will be a new mold coming out in 2011.

Apple announced next version of iPhone, called the iPhone 4 during the keynote by Apple’s CEO Steve Jobs’ at World Wide Developers Conference (WWDC10).

Jobs’ said: “It’s beyond a doubt, the most precise thing and one of the most beautiful things we’ve ever made”. There are new features of iPhone 4 as follows.

Updated design

The new iPhone 4 is 9.4mm thick and 24 precent thinner that the iPhone 3GS. It includes new camera with LED flash on the back with a second front facing camera as well. New volume buttons, a mute button and a second microphone on the top for noise cancellation. It has micro-SIM tray same as iPad.

iPhone 4 has three integrated antennas into the design: one for Bluetooth, one for Wi-Fi and GPS and one for UMTS and GSM.

Gorgeous Display

Apple introduces their first ever Retina display add much higher precision to the iPhone. In fact, at 326 pixels per inch, it’s double the 163 pixel per inch resolution of the iPhone 3GS. The display is same 3.5 inches with its length but at 960 by 640 it has four time as many pixels as the previous model. The 800:1 contrast ratio is also four times that of the iPhone 3GS, it uses IPS display technology as the iPad and the iMac for good color fidelity, brightness and viewing angle.

New Processor

iPhone 4 has the new A4 processor which is also the processor of iPad as well. This A4 processor is a tiny chip designed by Apple which occupied little space in the unit makes a welcoming room for bigger battery for iPhone 4. Apple says, it provides 40 percent more talk time. The company says the talk time is up from 5 hours to 7 hours; 6 hours to 3G browsing; 10 hours of Wi-Fi browsing; 10 hours of video; 40 hours of music; and 300 hours of standby.

The new iPhone is arsenic free, BFR-free mercury-free, PVC-free, and made from highly recyclable materials.

It comes in sizes up to 32GB of storage (the same as the iPhone 3GS) and includes quad-band HSPDPA/HSUPA networking with a maximum of 7.2Mbps down and 5.8 Mbps up.

“That’s theoretical because the carriers don’t support it yet,” said Jobs.

There’s also 802.11n Wi-Fi wireless networking, an improvement from 802.11g in the previous model.

Gyroscope

The new iPhone 4 adds three-axis gyroscope for measuring angular velocity. It can figure out pitch, roll and yaw; and rotation about gravity. The gyroscope plus the accelerometer provides six-axis motion sensing. There are also new CoreMotion API that developers can call for extremely precise position information which ideal for games.

All new Camera

iPhone 4 has a new 5 megapixel camera with 5x digital zoom and a LED flash. Not only that iPhone 4 also does a video with up to 720p HD video recording at 30 frames per second. You can even edit the video which you just shot right on your iPhone 4 with iMovie. You can add titles, changes themes, and use music from your iTunes library.

iMovie for iPhone will be available for $5 – “if we approve it,” Jobs joked, in reference to the App Store.

FaceTime

FaceTime is something you can video chat using the front facing camera and also with the back camera with a simple tap on screen to change what camera to use while video chat.

For Jobs’ patented (well, probably not, but it should be) One More Thing moment, he sat down on a chair to show off the iPhone 4’s video chatting capabilities. Using either of the two cameras, you can make video calls—a feature called FaceTime—between iPhone 4 phones over Wi-Fi only—at least through 2010. Jobs said Apple needs to “work a little bit with the cellular providers in the future”. You can switch between cameras and chat in landscape or portrait mode.

Price and availability

The iPhone 4 will come in black and white, at $199 for 16GB and $299 for 32GB. Apple will also add an 8GB iPhone 3GS for $99.

Jobs said that AT&T is going to make “an incredibly generous upgrade offer.” If your contract expires any time in 2010, you’re immediately eligible for that pricing, for up to six months early eligibility. The iPhone 4 will be available from Apple and AT&T’s retail and online stores, as well as at Best Buy and Wal-Mart stores.

The iPhone 4 goes on sale in the U.S., France, Germany, the U.K., and Japan on June 24, with pre-orders starting on June 15. It will ship in 18 more countries in July, in 24 more in August, and in 40 more by the end of September.

Apple also showed off some accessories: a $29 dock and a $29 case called a Bumper that comes in white, black, blue, green, orange, or pink.