A quick look at NGrain's web page suggests they need to get their act together a little.
They advertise multiple platform support for their core Ngrain SDK. Where multi-platform is defined as Vista, Windows 7 or Windows 8. Hmmm.
Then one notices that the web page prominently features what is clearly a MacBook Pro - albeit in mirror image, running Vergence. Guess what - Vista, Windows 7 or Windows 8 only as well. Sure, you can run those in a Mac, but it isn't a good look. (The Mac is clearly a mirror image - they keyboard layout is mirrored as well as the ports.)
In fairness they do seem to have a neat high performance 3D volume renderer that is perfect for augmented reality. However usually these tools are used with much more capable devices than low end glasses and iPads. Motion tracking being a key capability for a start.
There have been immersive 3D tools around for 20 odd years. Cartia, and Pro Mechanica's Windchill come to mind (or whatever they are called now - it has been a long time.)