Goals
• Sum up and formalize the previous steps’ outputs
• Establish the requisites that the system must accomplish

• Sum up and formalize the previous steps’ outputs
• Establish the requisites that the system must accomplish
The service design phase outputs an idea of a solution to the encountered problem; this solution needs the design and development of an interactive system that will be faced in the following phase. The documents and studies done so far are analysed and the decision of developing a mobile application on Android is taken.
Since the interactive system must be run in a portable device for making the orders anywhere a mobile application is chosen. Among the mobile platforms Android is selected since it is widely used and it is convenient for applications development and distribution.
For defining the requisites user stories are formulated. This method consists on a description that includes, in natural language, what the user needs or wants to achieve an objective and perform a task. They are based on the personas selected in the previous step, since each one of them has different necessities towards the system.
The user stories will be the inputs for the product design phase in order to ensure the success of the project and summarize the service design chapter.