Location is an important technology to enable new retail and smart city. While outdoor locations can be easily obtained using GPS, indoor localization presents great challenge to research community. In this talk, I will share our research results on how to sense one’s position in indoor space. I will discuss two approaches to achieve that: 1) based on app using phone sensors (as installed in an app), and 2) IoT-based sensors using RF and video. We have implemented the technologies and deployed them in various venues. By integrating our technologies with data analytics, vast commercial opportunities may be captured. I will share some of our experimental and deployment results, and the opportunities our location sensing technology enabled.