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More pointers for you as you are about to buy the Nexus 7 I hold near and dear as I own one myself.
Battery - The Nexus 7 has a large battery. As such a typical phone charger or power port on a computer will
never fully charge the device, be sure to have on hand the original wall charger and factory cable when you travel.
If you need a 12 volt option like a car adapter or portable power pack then make sure you buy one that outputs at least 2amps and use a high quality usb cable to power it. If you find yourself in a bind then be sure to turn off the tablet when it is charging else you will probably find the N7 using the power as it comes in.
Storage - If you plan on using the N7 as a host and distribution device to share tidbits of the trip with the family and friends then you will need to note that the N7
does not have removable media like an sdcard, nor does it have a port for it.
The N7 does have full USB host support, that is you can buy a special cable that will convert the micro usb port on the N7 into a full sized USB port that you can connect full sized devices like keyboards, mice, and more. You can also connect portable storage like USB drives and memory cards with the proper adapter.
You want an OTG device or cable like the following -
Decrescent 4 in 1 Micro USB Host OTG and Card Reader: Amazon.co.uk: Electronics
OR
TECHGEAR