Micromax Bolt D321 official Pictures. Micromax Bolt D321 is a Smartphone of micromax. The Micromax Bolt D321 Android Smartphone. Announced Feb 2015. Features 5.0″ Display, MT6572 Chipset, 5 MP Primary Camera, 2 MP Front Camera, 1800 MAh Battery, 4 GB Storage, 512 MB RAM. Micromax Bolt D321 price starts.