I have an iPad3 and dropbox is one of my favorite apps. Dropbox seems to be extremely useful, convenient and easy to use but I'm not sure if I'm using it properly. A few questions: 1.It seems that dropbox and iCloud are very similar (i.e. they are both used to share files). Is this correct and which one do you recommend? 2.Can I upload any files and apps from my iPad to Dropbox or just photos and videos? I have copied pdf and Excel files from my PC to dropbox, can I do the same with my iPad? 3.How can I transfer a book from iBooks, Stanza or Kindle to my PC? Can I use dropbox to do it? Thanks in advance!