Comparing iFrame and FBML Flash Facebook applications
The following table summarizes the differences when creating your Flash Platform application as an iFrame or FBML Facebook application. The two most significant differences are the ability to control the embedding of a Flash object and the ability to access scripts. Feature iFrame FBML Flash Player version and detection code You control the embedding. You write (or include) the JavaScript detection code and the selection of the required Flash Player version. Typically, SWFObject is used. You have no control over the embedding. Currently, the <FB:swf> tag requires Flash Player version 9.0.115 and there is no way to specify any other version. Script access Can be denied by setting allow_script_access=never .