Prior to the 6.1 update, users could only Like, Comment or tag users in a photo within the iOS app.
Facebook for iOS is a free download from the App Store. [Direct Link]What's New in Version 6.1
- Photo viewer button lets you save, share or make profile picture
- Improved places editing when checking in on iPhone
- Events load faster on iPhone
Article Link: Facebook for iOS Adds Sharing and Saving Options to Photo Viewer