E.ComKit is a collection of RealThing widgets that aims to make the design and prototyping of user interfaces for an online shopping mall significantly easier while supporting a new real world-based user interface model. E.ComKit widgets include shelves, product, product viewer, bag, cash, payment, delivery, etc. For making virtual shopping over the Internet, the user can manipulate and interact directly with these widgets as he does in a real-world shopping mall. Each widget dynamically and automatically varies its look-and-feel according to the cultural environment and user stereotype. Our objectives were to develop a prototype of E.ComKit based online eBookStore, and evaluate its usability compared to current online eBookStore, as well as to build specification of E.ComKit.