If you’d like to manage your smartphone from a PC then just connecting the two devices should help you get started. Your device should show up in the Computer folder, and you’ll be able to drag and drop files to it, just like any other drive.
Need more? Then you might want to consider the free Moborobo. File transfers, backups, imports and exports are just the start of its abilities, and – conveniently – the program works both with Android devices and the iPhone.