Had bought this for the reason of charging and exchanging data through the usb cable. Now when I received the product it only just did the transfer of the data and no charging at all. So that's why I give it the rating of 3 or 2.5 Stars cause it does half the job. It would've been useful if I could charge it that way I would use the usb device thing in my car to charge it when i didn't have time to charge it @ home and could save me time from waiting for my phone to charge on the usual power plug.