In the first place, it was the vivo NEX having a slider selfie shooter, after that, in just a week, Oppo Find X has come featuring all cameras tucked in the pop-up mechanism. Subsidiary nubia of ZTE has abandoned all of the moving parts and it has just put on a secondary display on the back of the nubia X in the race to have both good quality selfies and bezel-less display.

It seems probable that vivo has liked this idea very much, this is suggested by a photo leaked on Weibo, that displays that a NEX 2 is coming featuring one screen on each side. In addition to all that, it is also quite possible to have three back cameras.
By adding a second display, essentially the companies get rid of the need to have selfie shooters. You are able to take selfies or video call people by means of the back screen, at the same time as stick to work and entertainment on your giant front panel.

At this time, too much time is left till we can tell anything for sure about the specs, but the phone is most probably going to feature Snapdragon 845 chipset. In case vivo is going all-in, at that time are also supposed to get 8 GB RAM and very much storage. The main display seems to be same as that of the 6.59” AMOLED panel on the vivo NEX S, whereas the secondary appears to present 16:9 ratio so as to make some space for the vivo logo on the bottom and three cameras on top.