There is only one file type that uses the .JWPUB extension:
Jehovah's Witnesses Publication File
A JWPUB file is a digital ebook saved in the Jehovah's Witnesses Publication (JWPUB) format, which is used to save ebooks that can be read using the JW Library mobile app. It contains a digital publication, such as a bible translation, book, magazine, brochure, meeting workbook, or newsletter. JWPUB files are based on the open XML-based .EPUB format, which is commonly used to save digital books and publications.
JWPUB files are used exclusively by the JW Library app for Android and iOS mobile devices and for Windows platforms. The app allows Jehovah's Witnesses to receive and view various publications on their mobile devices.
Typically, users download the files directly from the JW Library app but may also download content published on jw.org as JWPUB files, then transfer them to their app or share the files with other users. Publications on jw.org may also be downloaded as .PDF and EPUB files.
JWPUB files can be manually opened with a Zip-decompression program. To open it, change the .jwpub file extension to .zip, then decompress it with a decompression program, such as Microsoft File Explorer, Apple Archive Utility, or Corel WinZip.
The extracted contents in the folder typically include a contents file, which includes the publication information, and a manifest.json file, which includes metadata about the JWPUB file in JSON format. After viewing the contents, rename the .zip file extension to .jwpub to open it again as a JWPUB file.
Updated: May 10, 2019