You can use Zotero on your mobile device by installing a "Bookmarklet," a special link that saves items directly to your Zotero account on the web. However, Zotero suggests that the desktop application be used for the best experience.
You must have a Zotero account, and your iPad must be online:
When you're on a page with a citation, select the Save to Zotero bookmark. The iPad browser will save the citation directly to your Zotero library online. For this example, we will be setting up the Zotero Bookmarklet on an iPad.
To install the Zotero Bookmarklet for Deskop, Chrome or Firefox for Android, the Android browser, or the Opera Mobile/Mini Browser, the method is very similar. Instructions for installing the Zotero Bookmarklet can be found here.