We all know the iPhone is the champion of free apps, but have you ever crossed over to the other side, the side of the paying? For (mostly) a nominal fee, you can buy apps to help you with everything, from  faster, better, stronger Twittering to budgeting for a brand new house to getting a personal trainer for less than five bucks. Though some of these apps cost more than others, the functionality and entertainment they offer will make each of them worth every hard-earned cent.

Interested in more apps for more mobile operating systems? Check out The Best Free Smart Phone Apps (And A Few Worth Paying For), our list of free and paid applications for Windows Mobile, BlackBerry, Apple, and Android devices.