The app is divided into two roles, one is a normal user role, and the other is an administrator role. Ordinary users can browse second-hand items that are not used by others. If you want, you can click the I want button and wait for the staff to approve it before recycling. The company fetches second-hand items it wants. Users can also publish second-hand items that they don't need, and release the second-hand items in their hands to recycling companies, waiting for the recycling company to take them away, so that resources can be recycled and reused.