This app was mentioned in 15 comments, with an average of 9.53 upvotes
There is a google cardboard app that lets you swap perspective with someone. Once the full featured VR comes out, and peripherals are made, you could probably simulate this pretty well. It wouldn't be perfect, obviously, but would still be trippy as fuck.
Honestly, if I had twitter I would follow them too. As it stands, I'll have to make do with Body Swap app for the really kinky shit.
Yes there is! I saw it linked here, tried it out, but I forget what it's called. I'll try using google or the search feature of Reddit.
Edit: yeah, here. https://play.google.com/store/apps/details?id=com.fofism.bodyswap
It swaps your bodies, pretty interesting experience.
Even if it wasn' t created with Gear VR in mind, Body Swap is the best app you can download if you have two cardboards/Gear.
https://play.google.com/store/apps/details?id=com.fofism.bodyswap&hl=it
If you sincronize you movements with your "body swap", the effect is at least.... WEIRD
You don't have to be facing it. Imagine attaching the camera to a drone? It's not really like a mirror other than one possible use of it. This app totally skips most of these steps for you though.
If you want to swap bodies, there's already an app for that! All you need is a pair of Google Cardboards and a wireless router.
Even if it wasn' t created with Gear VR in mind, Body Swap is the best app you can download if you have two cardboards/Gear. https://play.google.com/store/apps/details?id=com.fofism.bodyswap&hl=it If you sincronize you movements with your "body swap", the effect is at least.... WEIRD
Isn't this what Body Swap does? The app only works on the same wifi network atm. But, the developer is working on internet functionality (iirc, he's thinking about adding NAT traversal by using a TURN server due to issues with firewalls). Once that's finished, it seems to be exactly what you were thinking of doing.
In regards to the 3D, you could always go with fake 3D. Apart from the HTC Evo 3D and LG Optimus 3D (both released in 2011), there aren't many phones with 3D cameras. You could possibly use HTC's Dual Lens SDK (for the M8) to work out depth and, so, create a 3D image. But, that approach might add too much lag into the equation. I suppose that doesn't really matter if you don't want to add head tracking.
The webcam approach is probably the easiest. It would be best to make a 3D webcam using two HD cameras. Otherwise, you'll be limited to something like the Minoru which has a pretty poor resolution.
Apart from that, most AR Cardboard apps (e.g. Glitcher VR, Cmoar AR, VR AR) aren't multiplayer. They're all limited to a single user.
There's an app that is not meant to do that, but will work: Body Swap
There was an app out like this but I can't remember the name, wait... here it isbody swap
Body Swap, uses cameras, wi-fi, and streaming to have a second-person game where you see from the other person's perspective by /u/jesperht. Reddit thread
BeerBox, beer goggles simulator
https://play.google.com/store/apps/details?id=com.fofism.bodyswap&hl=en
body swap does this...but you have to be in the same room.