The mobile version of zotero.org allows you to access and edit your Zotero library on your tablet or mobile phone. While there are no official Zotero apps for mobile devices, there are several third party solutions.
The "Bookmarklet," is a special bookmark you can add to your browser that will allow you to save a page you are reading to your Zotero library.
You must have a Zotero account, and your tablet must be online in order to use Bookmarklet.
Now, when you're on a page with a citation, you can use the Save to Zotero bookmark to save the citation directly to your Zotero library online.