While it took the original iPhone 74 days to top one million units in sales, Apple announced last week that it has sold over 1.7 million iPhone 4 units in just three days; Steve Jobs said that this is the most successful product launch in Apple's history.

The iPhone 4 looks like a slab of stainless steel enclosed in two sheets of aluminosilicate glass, the same material -- according to Apple -- used in the windshields of helicopters and high-speed trains. The material is chemically strengthened to be 20 times stiffer and 30 times harder than plastic making it ultradurable and more scratch resistant than the previous iPhone models.

This minimalistic design makes the iPhone 4 looks elegantly expensive, but it also makes the phone less comfortable to hold and more prone to slips and drops.

I am a living witness of the iPhone 4's durability as I have already dropped it twice and yet there's not even a trace of scratch on the glass or dent on the stainless steel band around it.

Retina Display

The iPhone 4's most played up feature is the Retina Display. Apple claimed that the phone's screen resolution is so clear and too high for the human eye to perceive individual pixels. By developing pixels a mere 78 micrometers wide, Apple engineers were able to pack four times the number of pixels into the same 3.5-inch (diagonal) screen found on earlier iPhone models. The resulting pixel density of iPhone 4 — 326 pixels per inch — makes text and graphics look smooth and continuous at any size.

The Retina display uses technology called IPS (in-plane switching) — the same technology used in the Apple LED Cinema Display and iPad — to achieve a wider viewing angle than on typical LCDs. This means you can hold iPhone 4 almost any way you want and still get a brilliant picture. In addition, the Retina display offers four times the contrast ratio of previous models, so whites are brighter, blacks are darker.

Compared to other mobile device using AMOLED and Super AMOLED displays, you could barely see the difference with iPhone 4's Retina Display until you closely examine them. The iPhone 4's display is crispier and a lot clearer.

Gyro and accelerometer

iPhone 4 has a built-in three-axis gyroscope. When paired with the accelerometer, it makes iPhone 4 capable of advanced motion sensing such as user acceleration, full 3D attitude, and rotation rate. This means the phone could interpret more gestures and could have greater precision for better gaming experience.

Also with iPhone 4's Gyro and accelerometer, the website or graphics automatically fits on the screen when you tilt the phone.

Processor

The iPhone 4 is powered by the Apple A4 chip like all previous iPhone models, the chip is designed to be powerful yet power-efficient mobile processor. With it, iPhone 4 can easily perform complex jobs such as multitasking, editing video, and placing FaceTime calls. The Apple A4 is also used in the iPad where it is clocked at its rated speed of 1 GHz.

"Death Grip"

One issue that plagues the iPhone 4 is the signal degradation problem when you hold it in a certain way. This happens when you hold the phone with your left hand with the thumb touching the upper part of the metal band and the other fingers touching the middle and lower part of the metal band.

I was able to see the problem and yes the signal flactuated when I did it, but this is not the normal way to hold a phone, I have yet to see someone use his phone this way. I never used this kind of grip when I use a phone and I would never make a call using this style. I tried holding it the normal way and I did not encounter the "death grip" problem.

The bottomline: don't worry about this issue that has received a lot of airtime, it's there but you won't even notice it.

So, should I buy the iPhone 4? I would, and I suggest those who has extra Benjamins to get theirs, too.

Oh, and yes, MB Technews already got one.