The iPhone retina display is considered the most advanced display in a portable device, and one of the most unique iPhone 4 features. Apple introduced the new retina display with the iPhone 4 in June 2010 and revolutionized the cell phone display industry once again.
Moreover, Apple used used a high strength scratch proof glass screen to the front and back of the iPhone 4 to protect the retina display. Therefore, it is theoretically not necessary to add any kind of an iPhone screen protector to the iPhone screen.
Why called retina display?
The iPhone retina display was called after the eye retina. The eye can see some level of details to some maximum. After that maximum detail, no matter how high the resolution is, the human eye retina can't differentiate anymore. Therefore, the iPhone 4 retina display came after this theory, that the maximum possible details that the human eye can see in the iPhone screen has been reached.
That is the human retina can read the smallest text on this display, while any smaller text than what the retina display can provide can't be read anyway's by the human eye retina ability. Read this article about Apple's retina display.
What is the retina display resolution?
One of my wishes was always to have a high resolution screen on my iPhone. I was hoping that Apple increase the iPhone resolution to something like a VGA resolution of 640 x 480 pixels. That was my dream resolution for the least compared to the iPhone 3G/3GS resolution of 320 x 480 pixels.
The iPhone retina display was a dream that came true. It was more than what I was hoping for and it is simply an amazing display. A stunning 640 x 960 pixels resolution. That is basically (320 x 2 = 640 by 480 x 2 = 960) of the current iPhone 3G and iPhone 3GS display.
If there is nothing you like about the iPhone 4, then diffenetly you will love the retina display, and you will not quit looking at your iPhone high definition screen.
There is so much details in the iPhone 4 retina display that you can challenge your friends to read the smallest text possible on a website displayed with Mobile Safari. If they can't read the smallest text, then simply bring a magnifying glass, and you will be able to read the text. It is that much resolution in the retina display.
The new iPhone 4 display has four times the number of pixels per the same area od the previous iPhone 3G and 3GS. So you have the same 3.5" screen size but with four times the number of pixels which improves the details dramatically.
With the iPhone 3G/3GS, I had to zoom in a web page to read all the small texts to make them clearer. However, with the iPhone retina display, I can simply read the whole page without zooming. Of course, if you want to read a full story, you must zoom but for general quick browsing, zooming is not necessary any more.
For example, if I am looking for a contact in a page or a "contact us" area, I can simply look closer in the iPhone 4 screen, and find the contact area and click it without multiple zooming.
There is no other phone in the market at the time of the iPhone 4 that provide this high resolution. The iPhone 4 was the first to introduce such aggressive resolution that looking at any other phone screen just looked humble compared to the iPhone 4 display.
Apple did a great job with the iPhone 4 display without sacrificing the quality of the iOS. All iPhone applications worked on the new display without any problems or any necessary upgrades. Some iPhone applications automatically took advantage of the higher resolution without any any updates to the application, while others worked fine but with a little update from the App Store the display of the application improves dramatically in terms of details shown in the application, and pictures viewed.
I think with the iPhone retina display, I seriously reached my limit in terms of resolution for a portable device. I don't think I need any higher resolution any more. The level of details the iPhone retina display has is very close to holding a printed piece of paper or a magazine.