Xiaomi Redmi 3S is the cheapest phone in the market with good capabilities and great performance. I bought this phone because of its cool features like 2GB RAM and Snapdragon 450 octa-core CPU. This phone has got gyroscope feature in it which helps to connect with the VR, so that we experience the Virtual Reality with this low cost phone. It's got a larger battery capacity compared to other phones in this price range, which gives me a gud battery backup of 2 days on a standby and 1 day while on call and Internet. I recommend you to buy this phone if u r looking for the cheapest phone in the market.
