I'm using an original Kindle Fire tablet as the monitor for my front door security camera, but I didn't want to commit to anything as permanent as mounting it to the front door or a wall, so I figured I'd mount it on a stand near the door, and a microphone stand seemed like a good solution for that. The mount fits into a specific mic clip* (though you could probably design a mount that just threads directly onto the top of the stand), allows the tablet to swivel from portrait to landscape (the skate bearing is probably overkill), and the mount can be adjusted to fit different-sized tablets just by using different-length bolts (I suppose it may still be limited to tablets of a similar aspect ratio).
*Update: The mic clip was rubber, so the tablet was leaning over to one side which was annoying me, so I designed a new, rigid plastic clip.
Print one each of the "mic" and center, 2 each of the corner parts "1" and "2". Only the corner parts really need support, though the bottom (top as oriented for printing) of the mic has some big overhangs that droop somewhat.
The new mic clips are optional, but also require support.
When the mount swivels to portrait mode, the charging port is on the right side. If you want it on the left, create a mirror flipped version of the mic before printing.
This design incorporates a number of non-printed parts:
This mic clip: http://www.musiciansfriend.com/pro-audio/musicians-gear-heavy-duty-basic-mic-clip
1 608ZZ bearing
4 1/4"-20 x 4" hex bolts
8 1/4"-20 hex nuts
2 M4 screws (30 or 35mm long)
1 M8-1.25 bolt (anywhere from 50 to 70mm?)
at least 1 M8-1.25 nut
The printed plastic mic clip has holes for 2 M3 bolts (5-10mm long) and 3 zip ties (the ones I have were to brittle to fit, but it seems they aren't necessary for clamping).
(if you want to use all metric or all imperial hardware you'll have to make adjustments to some hole sizes, this was just what they had at my local Lowe's)
You can start by pressing the bearing into the center and pressing at least one of the M8 nuts into the bottom of the mic. Screw the M4 screws into the vertical holes in the center, they're the stops for the swiveling. Fit the center and mic together so that the screws are in the longer of the two slots, then insert and thread in the M8 bolt. Fit the "mic" into the mic clip on the stand (you can maybe wrap a ziptie around it for extra security). Insert the 1/4" nuts into the holes in the center, then slide a #1 and #2 corner part over a pair of the 4" bolts and start threading them into one side of the center. The bolts should stick out about 5mm into the big center hole. Rotate the center to portrait if it isn't already, and insert the tablet. Then install the top bolts and corner parts (tight enough that it doesn't wobble or wiggle, but you probably don't want to crush the tablet).