1. Create a new app at the following URL:https://developers.facebook.com/apps (note: Create new app button is located in the top right corner of this page)
2. Name your app (example: 'Your Store Product Comments'), leave the other fields empty and click Continue.
3. On the application settings page, click 'Website with Facebook login' under the 'Select how your app integrates with Facebook' section and enter your mobile catalog URL in the 'Site URL' input field.
4. Then enter your mobile catalog domain into 'App domains' under the 'Basic info' section. The domain name should contain only domain-related part of the mobile catalog URL (without 'HTTP' and without the path). For example, if your mobile catalog URL is 'http://m.example.com/my-catalog', the domain would be .example.com' .
5. Write down your APP ID and save it.
6. Go to the StoreFront Backend, click System Settings - > Social Tools -> FB Comments
7. Click Enable next to Show FB Comments and include the app id you wrote down in Step 5.
8. Click Save
9. You can now moderate your comments at this URL:http://developers.facebook.com/tools/comments
Screenshot (an example of app settings):