Almost a joke
A good start considering theres little else out there, but here are the main problems:
1) No way to upload a large amount of files. You are forced to manually select one file at a time through their stupid web interface.
2) No way to transfer lots of files (or any files at all) via normal file sync through through USB/iTunes, and then choose to protect your files once they are on the iphone
3) No folder structure.
4) You are forced to view your protected files within their own media browser app. Again, this means you cannot select existing files (other than pictures, it seems they allow you to browse your photo folder) and then protect them from within the iphone.
Its a good program for basic, beginner protection of a few individual files, but other than that it is a joke.
Danations about
Folder Lock, v1.5.5