I've been using a 16 gig Nexus 7 since August. Only $200, with a terrific Hi Rez display (Higher rez man iPad Mini, but less saturation). For $300, you can get the 32 gig with G3 connection.
It's slimmer than the mini, making it easier to hold. I've used it with an OTG cable tethering with D800E, but found it more convenient to use EyeFi card to download small jpeg shots for near instantaneous viewing and focus evaluation.
Using OTG cable & thumbdrive, (with Nexus media software) you can view large photo collections when out of range of wifi (clumbsy software though). Much better use is watching RIPPED movies. Of course there are the popular cloud viewing apps too.