Summary

Update-January 6 2017: I cannot no longer recommend using the charger/receiver combination below. Mine has either failed (after 11 months) or the IOS 10 update is somehow preventing it from charging now. I am now charging my Ipad the old way with the lightning cable.

Charging stand for 7-8" tablet, using PowerBot charger. Shown is Ipad Mini 2.

Use layflat function in Slic3r to lay the stand on it's back for printing - no support material required.
Photos show a stand printed in silver PLA with 20% infill.
At 30mm/s, the print takes 4.5 hours.
At 100% scale, the opening in the stand for the charger disk is 70mm diameter by 11mm thick.
PowerBot disk is attached with small squares of double-sided foam tape.
Some single-sided adhesive foam is used on the bottom supports where the Ipad rests.

Wireless receiver for Apple lightning connector here:
http://www.amazon.com/gp/product/B00OTW7RV0

PowerBot charger is available here:
http://www.amazon.com/gp/product/B00F6SQ1D6