title_body: Upload & Read eBooks in Chrome (i.e. Maintain a Cloud Library)
upvoted_answer: Have you tried the Kindle Web Reader? Kindle supports MOBI and you can import personal documents into your Kindle Library via an email address that is attached to your Amazon/Kindle ID.
  
  You can access your Kindle library through a web browser, and if you use Chrome, there is a Chrome App that supports Offline reading. I believe your personal documents will be synched across devices just like native Kindle books.