Epublib is a Java library for managing epub files. It is capable of reading and writing epub files programmatically and from the command-line tool. Epublib consists of two parts: the core and tools. The core runs both on Android and a standard JVM. Tools require a standard Java environment. Other features include a builtin Swing-based viewer and comprehensive coverage of the epub standard, supporting the spine, the table of contents, and the guide. The API is designed to be as simple as possible, while at the same time making complex things possible too.