LINK TO SITE
Podio is a "freemium" cloud-based collaboration service that's now owned by Citrix. It's currently a social collaboration tool where team members can set up flexible, effective workflows and manage projects.
Podio is "social" in that users can post statuses, make comments, "like" each others' posts, and share files. There is a comprehensive online help area.
Available for iOS and Android in multiple languages.