Apple iPhone 4 Dock - Manual (Page 3)

English 3
iPhone 4 Dock
Use the iPhone 4 Dock to charge iPhone, sync iPhone with
your computer, and play music on iPhone through external
speakers.
To charge iPhone and sync it with your computer:
1 Connect the dock to a USB 2.0 port on your computer (not
on your keyboard), using the cable that came with iPhone.