Attach Files to Comments on Feed Posts

It’s now possible to attach files directly to comments on feed posts using the Salesforce1 mobile browser app, as well as the Salesforce1 downloadable apps. Users can attach files from Salesforce or files stored on a mobile device.
Files available in: Group, Professional, Enterprise, Performance, Unlimited, Contact Manager, and Developer Editions

To attach a file to a comment, tap Attach a File icon. A preview of the attached file displays in a new comment on the post.

Screenshot of attaching a File to a comment