Our ability to collect data in various sensors, devices, formats, either from independent or connected applications, has signiﬁcantly outpaced our capability to process, analyze, store and understand these datasets. Considering Internet data, the web pages indexed by Google were 1 million in 1998, but quickly reached 1 billion in 2000 and have exceeded 1 trillion in 2008. Recently, the ﬂourish of social networking applications, like Facebook, Twitter, that allow users to create contents freely, further ampliﬁes the already huge web volume. Furthermore, with mobile phones becoming the sensory gateway to get real-time data on people from different aspects, the vast amount of data that mobile carrier can potentially process to improve our daily life has signiﬁcantly outpaced our past CDR (call data record)-based processing for billing purposes only. It can be foreseen that Internet of things (IoT) applications will raise the scale of data to an unprecedented level. People and devices (from home coffee machines to cars, to buses, railway stations and airports) are all loosely connected. Trillions of such connected components will generate a huge data ocean, and valuable information must be discovered from the data to help improve quality of life and make our world a better place. For example, after we get up every morning, in order to optimize our commute time to work and complete the optimization before we arrive at ofﬁce, the system needs to process information from trafﬁc, weather, construction, police activities to our calendar schedules, and perform deep optimization under the tight time constraints. In all these applications, we are facing signiﬁcant challenges in leveraging the vast amount of data, including challenges in (1) system (2) algorithm (3) business model – application. This workshop aims to bring together people from both academia and industry to present their most recent work related to these issues, and exchange ideas and thoughts in order to advance this big challenge that has been considered as one of the most exciting opportunities in the past 10 years.