Collapsible Smartphone VR Goggles

This is my take on the Google Cardboard idea – a frame with lenses that very inexpensively turns your phone into a pair of VR goggles, like a very low budget Oculus Rift. Google Cardboard is very bulky though, and makes it hard to use the touchscreen while the phone is inside. It's also impractical to transport. So I made this.

Features:
* collapsible – it's only slightly larger than a Galaxy Note 2 when collapsed
* add a magnet (diameter 20mm or less) and a washer (diameter 20mm) for a magnetic switch (to interact with apps via the phone's magnetometer) like the one that Google Cardboard offers
* uses inexpensive Google Cardboard lenses (e.g. from eBay, see below)
* lenses can be focused individually
* attachment points for a head strap
* compatible with Google Cardboard apps
* frame can be adjusted to six different phone sizes (1 to 6) – a LG G2 sits at size 3, a Galaxy Note 2 at size 5
* display stays accessible (mostly; i wouldn't type a text on it, but selecting things