Fully conformant EPUB 3 support
Readium should implement 100% of the functionality required by the EPUB 3 specification. A number of features and behaviors are MIA from the initial proof-of-concept.
Support for all optional EPUB 3 functionality
Support for emerging EPUB features
Readium should be a testbed for newly proposed EPUB specifications such as fixed-layout metadata, CSS Page Templates, dictionaries, indexes, etc.
Screen-reader integration on Mac & Windows is top priority here.
Localization of Chrome Extensions is a well-defined process, so let's get Readium Chrome Extension for other languages. Once we have i18n framework set up, we could use non-technical help for creating UI strings.
Could be an entirely separate codebase from Chrome Extension configuration. Unlike Chrome Extension, could include a "fork" of WebKit to address issues at that level. Note that apps to be distributed via Android Market for smartphones and multi-purpose tablets may have quite different requirements than dedicated eReader devices based on Android (the latter may have significantly reduced performance, lower memory, e-ink display, etc.).
Could be an entirely separate codebase from Chrome Extension configuration. Needs to abide by Apple licensing restrictions against integrating a different WebKit than built-in to iOS, as well as against using private APIs.
WebKit has some bugs and issues in Japanese typography. Readium should pursue addressing this, ideally getting fixes into WebKit itself.
UX Refinement / User Features
While it's not a goal for Readium to be a production-level consumer Reading System we'd like to illustrate best practices and make the Chrome Extension and other configurations easy to use. Features to consider include:
- Default font, font size, color
- Day / night mode
- Default margins
- Default page transition (none, slide, curl, ...)
- Drag & drop content into library view
- register .epub file extension with system OS's so double-click opens in Chrome+Readium
- preference setting or other way for user to control whether newly open EPUB files are automatically added to Readium library
- integrated acquisition (e.g. OPDS support, built-in feeds to free content)
Chrome Extension specific feature support
Ideally based on EPUB 3 CFI spec, perhaps utilizing schema proposed by Adobe (compatible with Adobe Digital Editions).
Additional developer-mode features
TBD to meet needs of content developers.
Using PhoneGap or similar framework, enable an EPUB publication plus Readium to be packaged into a book/app.