A new feature found in iOS 5 is the ability to turn on private browsing for Mobile Safari. Once private browsing is activated, Mobile Safari will stop keeping history of your Web browsing. This can come in handy in a number of various situations, for example; letting a friend borrow your iOS device to check their e-mail. Having private browsing turned on will ensure their personal info isn't stored on your device, providing them with piece of mind.
The picture above shows what users have grown accustom to seeing when using Mobile Safari. Notice the bar on the top and bottom are either gray or blue. With iOS 5, this is always a quick way of knowing if you currently have private browsing turned on.
To turn on private browsing, first open the Settings app and then scroll down and select Safari.
Once Safari is selected you will see a toggle switch to turn on Private Browsing. Turn it on by moving the switch over. Once it's turned on you will be presented with an option to keep your existing tabs open in Safari, or to close them. Once you have selected to leave the tabs alone or close them, launch Safari.
As you can see, the bars that were previously light-colored, are now black. This indicates that your iOS device has private browsing currently enabled.
Repeat the instructions to turn private browsing off and have Mobile Safari restore your last, public browsing session.
While deleting browsing history,, is just as effective as a private browsing mode, it is only effective when you remember to go in and delete your history. Private browsing is one switch, with one setting. The fact that the color of the browsers appearance is such a drastic change, it will be easier for users to remember to go back and turn the feature on or off.