ReadEra is described as 'Read book files in EPUB, PDF, DOC, DOCX, RTF, TXT, DJVU, FB2, MOBI and CHM formats. Supports chapters, bookmarks, page style. Saves the current reading position. Automatic detection and display of the list of all supported documents on your device' and is an app in the News & Books category. There are more than 50 alternatives to ReadEra for a variety of platforms, including Android, iPhone, Windows, Android Tablet and iPad. The best alternative is calibre, which is both free and Open Source. Other great apps like ReadEra are Okular (Free, Open Source), Amazon Kindle (Free), FBReader (Freemium) and Moon+ Reader (Freemium).