Redmi Note 4 uses a noise-eliminating CMOS sensor with backside illumination (BSI) and larger pixels to give you stunning images even in low light. It also comes with Phase Detection Autofocus (PDAF) for 0.1s ultra-fast focusing, which is especially useful for shooting moving objects. The 2.5D curved glass has an aesthetic edge over typical flat glass. It looks better and feels a lot smoother when you tap and swipe your fingers across the screen. Glossy CNC-finished separation lines made of anodised aluminium add a touch of class to Redmi Note 4.