The "University Used Books" app is mainly used to provide students with an online platform for buy and sell used books. On this platform, students can exchange and purchase second-hand books by publishing book information and attaching personal contact information.

Main functions:

1. Registration and login
2. Main interface and classification interface The main interface displays all used books in chronological order. It is the first interface displayed after login. The classification interface is displayed by book type. You can quickly find the books you want by selecting the four categories of "computer, mathematics, economics and literature".
3. Release idle books Publish the books you want to sell, fill in the book name, new and old status, book classification, price, contact information, etc.
4. Personal Center Manage personal accounts, including personal information, password modification, favorites, logout, etc.