BAsic recommendation: Facebook applications should NEVER be considered safe to use. While many are perfectly harmless, if somewhat inane, they can easily contain virues and other nasty software you don't need to catch. Facebook warns you that all of your information, photos, etc., can be made available to applications you use, and you have no control over it when that happens, none, zip, zilch, nada. All the groupings and controls you apply are then worthless.