A little background: I own four plots totaling over 100 acres. Among these parcels of land I run 10 trail cameras, seven of which are on my two main hunting grounds.
Dorky as it seems I typically bring my laptop into the woods when simply checking cameras. It has an SD card slot (which is why I don't buy Apple laptops anymore - Thanks Jony Ive!) This lets me view the pictures and keep them for archiving at home. (My home NAS drive has hundreds of game videos dating back to 2013).
Now, when I'm hunting and don't want to drag around a laptop, I use a 7" Kindle Fire. I can view all photos and videos and store them to bring home. This Kindle Fire (which is going for about $29) also lets me read and play games while in the blind/stand. Since the Kindle has a microSD slot, I make a point of buying microSD cards with the adapter. They're the same price as the miniSD cards, at it allows me to use either the miniSD (laptop) or microSD (Kindle) for reading.
I don't understand the appeal of buying a dedicated SD card reader. They generally cost more than a Kindle and do far less.