1. Rich Text Editor: option to choose paste as plain or html
2. Insert audio and video to Rich Table
3. Insert audio and video to Question
4. Instant Preview in Markdown Editor (iPad & Mac)
5. Instant Preview in HTML Editor (iPad & Mac)
6. Scan Document: support images
7. More keyboard shortcuts for question and slideshow
8. External Widget can be hidden and launched via link
9. Sort books by author
10. UI refinement
11. Bug fix
