If you are developing a smartphone or handheld application, you can use Adobe Reader Mobile SDK (RMSDK) to build a fully-customizable eBook app that is compatible with Adobe Content Server.
The Adobe Reader Mobile SDK (RMSDK) is a programming toolkit which enables applciation developers to render PDF and EPUB content on their devices. It also supports Adobe's eBook content protection model and is compatible with the Adobe Content Server. The RMSDK has a much smaller footprint than the Adobe PDF Library SDK; consumes less power, and is generally optimized for use in handheld devices.
Learn more about the Adobe Mobile Reader SDK.