A book, especially reference books, need to have the ability to accept highlighting and scribbling of notes. I do that all the time on other ebooks, but Safari books To Go app has no such functionality at all. At best, I can tag or bookmark a page, but it requires me to be online. I just want to highlight a line, not the whole page. I do read on the go, in a plane, at the pool where a connections is hard to come by.
Highlights and notes from your desktop does not sync with this. A very poorly designed reader.