NIU Tek 4D2 official Pictures. NIU Tek 4D2 is a Smartphone of niu. The NIU Tek 4D2 Android Smartphone. Announced Aug 2014. Features 4.0″ Display, MT6572M Chipset, 3.15 MP Primary Camera, 1.3 MP Front Camera, 1200 MAh Battery, 4 GB Storage, 512 MB RAM. NIU Tek 4D2 price starts.