YunOS is a Linux-based mobile operating system developed by AliCloud, a subsidiary of Alibaba Group. Its latest version “YunOS 5 ATOM” was published in China in 2015, to power smartphones, set-top boxes, smart cars, wearables, and IoT devices. YunOS smartphones witnessed strong growth in 2015. We forecast the accumulative shipments of YunOS powered smartphones will top 100 million units in 2016. What are key drivers behind the explosive growth? What challenges does it face ahead? Will it challenge Android in global smartphone market?