Facebook now allows creating and adding "Test Users" to your apps from the Developer Site. "Test Users are invisible user accounts associated with an app created for the purpose of testing the functionality of that app. Test Users are not visible by others on Facebook; They can only be friends with other Test Users, but can still experience your app as a regular user," informs Chris Dentel, memeber of Facebook developers team.
"To get started, go to the Roles page on the Developer App. A new role, "Test Users," has been added. Click the "Add" link in the Test Users section to create new Test Users. In the "Add New Test Users" dialog, specify the number of Test Users to add. You can also authorize the Test Users for your app so that they are ready to begin using your app immediately. Otherwise, your Test Users will have to go through the standard permission dialog. After your Test Users have been added, you will be taken to the "Manage Test Users" page."
From here, you can:
- Edit names of Test Users (Click name to edit). Clicking Test User name prompts a dialog that allows you to customize the name (e.g., Chris Test).
- Make all of the selected Test Users friends (Make Friends). Making Test Users friends with each other simplifies testing the social aspects of your app (e.g., sharing content with friends, sending requests, etc.).
- Add the selected Test Users to another app that you own (Add to App). When adding Test Users to another app, you're also given the chance to authorize them for that app. You can also select multiple apps to add the Test Users to.
- Remove the Test Users from this app (Remove). Removing a test user only removes it from the current app. If the Test User is a Test User for another app, it will remain a Test User for that app. Generate an access token (Show Token). Click "Show Token" to fetch an access token for that specific Test User.
To begin using your app as a Test User, click on the "Switch To" link. This will log you out of your account and log you in as your Test User with just one click. From here, you can customize your Test User further or begin testing your app.
When you are finished with your Test Users, you can delete them or keep them for later testing.
[Source: Facebook Developers]