iPad only: The iPad is a device destined to be handed over to friends and passed among family members, but there are no user accounts or variable browser settings. Enter Switch, a clever browser that allows user accounts and anonymous guest browsing.
At its core, Switch sets up password-protected user accounts for a browser that show up whenever Switch is started up, or when returning from a screen lock. That alone makes it worth the current $1.19 price for many, but Switch has a few other tricks up its sleeve. Most helpful to iPad owners, who have a seeming obligation to show the device to their tablet-less friends, is a guest mode that doesn't mess with settings and wipes away history, cookies and passwords whenever the guest is done.
Switch also offers multiple logins and passwords for individual sites, so those with multiple Twitter accounts, commenter logins, or other site credentials can switch between them at will.
Switch is $1.19 for a limited time in the iTunes Market, and is for iPads only. If you're far from the only one who touches their own iPad every week, it seems like a must-buy.