Zoo for Zotero is a free and open-source program that lets you view your Zotero libraries on your Android device. It offers a modern and fast interface that supports collections, group libraries, webDAV, searching, and annotation syncing for attachments. The app caches the library and only syncs changes, making it friendly to large libraries after the initial sync.

The program currently only supports using the official Zotero Account Syncing. It is a hobby/passion project of the developer, Michael Johnston, who welcomes feedback and contributions.

If you are a Zotero user and want to access your libraries on the go, Zoo for Zotero is a great option to consider.