We use this on long car trips were not only do my husband and I have a cell phone to charge, but my daughter is usually along, so add a third cell phone, my grandduaghter is using the after market DVD player that is strapped to the head rest, and then we have an old IPOD loaded up with Disney movies for her. My husband plugs into the regular Ipod/Iphone doc on the dashboard and this device opens the single charger up to 4 devices. What a life saver with small kids along!!!!