Browsing the Internet on your iPhone or iPod Touch is super convenient, but at times it can be a bit frustrating. The screen size isn't ideal for consuming large amounts of information on some Web sites. Even if you turned your iPhone on its side to view it in landscape mode, the top address bar and bottom controls took up much of the screen.
With iOS 6, Apple has addressed this problem by introducing a full-screen mode for browsing the Web in landscape mode on the iPhone and iPod Touch.
When using Safari, assuming you don't have the autorotate lock enabled, turn your iPhone on its side to rotate the screen into landscape mode.

In the lower-right corner you will see a button consisting of two arrows pointing in opposite directions. Tap on the button to enable full-screen mode.
The address bar and the bottom buttons will disappear, leaving a transparent arrow in one corner acting as the back button while you browse. In the other corner there will be a transparent button with two arrows pointing at each other. Touching it will disable full-screen browsing.