I look forward to receiving my developer kit to compare it to the NEODiVR solution for the iPhone 6s Plus/Occipital Structure sensor that allows for eAVR (environmental Awareness Virtual Reality) that I have designed the NEODiVR for to allow you walk, sit, crouch, and even lie down in the VR environment. With my new NEODiVR "Lopue" for 5.5" I have also decided to design a version specifically for the Intel and Lenovo Project Tango phones.
Battery I am not too concerned with since adding a external battery pack is an easy solution. So my concern would be with overheating like the Samsung phones. Something I don't have to worry about with the iPhone.
Also, UHD or higher screen resolution allows for it to be used as VR device, which is why it was made to be Project Tango compatible with high performance IMU.