ePUB3 specifications have been released on 11 October by IDPF.
Here is a brief overview of the new features that will allow more complex layouts, rich media support and better typography
Linking : New standardized way of linking may allow sharing of bookmarks and location across various devices
Style sheets : Support for multiple style sheets which enable both horizontal and vertical layout and both left-to-right and right-to-left writing. May allow users to select between day/night reading views
Multimedia support: Support for new Video and audio elements. Will allow media overlay like ability to synchronize audio with text narration. Maybe like Fixed format layout books for iPad ?
Fonts : Support for OpenType and WOFF fonts. Font embedding supported.
Scripting : Possible
Text to Speech : Automatic text to speech conversion.
Support for Dynamic Layout : Content can be formatted on the fly for the intended device instead of fixed pagination.
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