I have the NuGuard GripStand
for both of my full size iPads. This is a very well made, sturdy stand that easily switches between portrait and landscape modes. Because of the design, it is also surprisingly well balanced to use on non-flat surfaces too like a bed or couch. You can also easily pivot the stand to any degree you want which is very handy. Sometimes a minor adjustment in tilt is all that's needed to get rid of glare from overhead lights or windows.
The ring on the back also acts as a handle, or you can just remove it and use the iPad in the rear shell alone. The shell is very strong and saved one of my iPads from being destroyed when my son dropped it on a concrete floor.
Unlike many of the other desk stands, the GripStand remains attached to the iPad and you don't have to fuss with carrying a separate, detached stand. It is also very versatile in that it comes with a strap that you can use to attach it to the back of a car's headrest and an optional base is available if you want the iPad to sit at a more raised height like a monitor for use as an LCD picture frame or other display purposes.