Why there may be limited functionality on an app

Applications that access certain platform features must comply with our Developer Data Use Policy. If an app violates the policy, the app’s access to these features will be disabled and the app may not be available for download. If you have already downloaded this app, you may still continue using it, but some features or functionality may be disabled. For example, your avatar may not appear or you may not see your friends list in the app. The disabled features and functionality will return as soon as the app is back in compliance.