In this project, We developed a mobile phone app to remind elderly people not to eat outdated food. We did not only concern about how people can achieve the task on the app, but also consider how they can easily access to different functions  on the app without struggling to read any user manuals.

We thought about the problem from a systematic perspective and apply design theories to solve the problem. 

But first and foremost, the fundamental problem for design  is to define user's goal. It's the question regarding why and what they need versus how to achieive the function.