Originally designed for an iPad 3, but fits the iPad 4 as it's the exact same dimensions.
UPDATE: A new thing has been created for the iPad Air 2 stand: http://www.thingiverse.com/thing:989878
UPDATE: I've uploaded "iPad 2 Stand.stl" use this if you have an iPad 2.
I wanted a stand that would hold the iPad both in Portrait (with home button accessible) and Landscape. I came across thing 23758 by tealid but it was very square looking and the back support required support material which made it look unfinished.
First version I made was just slightly rounded in Tinkercad. But have sinced learned Solidworks which is much more powerful.
Pictures/STL attached are of the much improved Solidworks model, but feel free to use the Tinkercad object.
Download "xxx_test.stl" where xxx is the base filename. These are CUT versions using NetFabb Studio for the slot size. As everyone's printer is different, once you determine which slot best fits your iPad. Download the full STL that matches the "_test" version. I've included what I use (9.4mm) as well as .1mm, .2mm, .3mm larger slots. I hope that'll be enough to take into account printer variations. If someone wants an even larger size slot let me know.
I have my printer calibrated pretty well, the size of the slot was generated at 9.4mm (8.6mm for iPad 2) which is what Apple lists as the thickness of the iPad.
iPad Stand.stl -> Slot is 9.4mm, after which additional files: _9.4mm+.1,9.4mm+.2,9.4mm+.3
iPad 2 Stand.stl -> Slot is 8.6mm, after which additional files: _8.6mm+.1,8.6mm+.2,8.6mm+.3
Above files are the base files +.1mm-.3mm larger. The 9.4+.1 and above the slot was moved back .2mm.
NOTE: The "ridge" that is seen in the middle of the iPad embossing text on the front has to do with Skeinforge making that entire layer a bridge. I'm not sure of a way to get rid of that.
Printed at .27 layer height, 10% Infill, Extra Shells 2 (3 in total) on a Replicator 1 using ABS. Print, wait to cool, remove and insert iPad :) Depending on your retraction settings you may want to smooth out/wet sand the slot where the iPad goes so not to scratch it.
Holds the iPad in Portrait (with the home button accessible) or in Landscape.
Originally designed using Tinkercad:
Later redesigned in Solidworks (you can make much smoother objects because of the Fillet functionality) among other things!