You can add a High Quality Car USB Charger to plug in to the 12v socket giving 4 usb ports
This charger will allow you to power 2 USB peripherals at any one time. Will work on any device that is powered directly via USB.
Bottom USB port is 1A (DC 5.0V) which can be used to charge mobile phones
Top USB Port is 2.1A (DC 5.0V) which can be used to charge tables such as iPad, iPad Mini etc
Both USB ports can be used at the same time
Short Circuit Protection
Automatic Overload Cut-Off
Ideal for charging Apple iPad, iPhone, Samsung, Nokia, HTC, Sat Nav, MP3, MP4 players, Digital cameras and various other USB powered devices.
Approximate size 6.0×3.1cm