Secondly, the design and assessment stage is considered. The materials for early-stage strategy and user analysis can be effectively used only after they are analysed in a systematic way and expressed in a refined way. Object modelling, which is one of the methods, means classifying the results of strategy and user analysis according to the object determined before and vividly describing its attribute, behaviour and relation in the form of graph. The abstract object model can be gradually transformed into user interface views in different specific extents, i.e. low fidelity model and high fidelity model. After the design model is built, some means and methods are needed to verify whether the represented model matches with the ideal user model. The user availability test and expert assessment are two of such methods. The user test method is to show the design model to the target users and obtain the users’ feedback data through users’ simulated use or discussion etc. The expert assessment method is to invite experts in human-computer interface design and system function to examine the design model according to their experience and then point out the availability issues. The final stage is implementation and assessment and task analysis. This stage, which is the final high fidelity model after several times of iterative designs, is to conduct the interface visual design based on the enterprise’s own design style and specification. After interface design, a comprehensive technical test and user test on the project are required to guarantee the maximal perfectness of product before it comes into the market. After the product is put into the market, the designer usually needs to collect all sorts of user feedbacks. Such information collection and processing not only can help the sales and market operation of current product but also can help the improvement, optimization and future updating of product. Therefore, in this stage, user tests should be carried out for several times in different stages or other ways should be used to track the users’ use condition and satisfaction degree.