I\'m reading facebook Android API 3.0 documents, and I do not understand what does session has to do with background activities. In all examples I\'m supposed to extend \"Facebo
You do not need to inherit from anything, if you don't provide an app_id through code, you must specify it in your application metadata (and in your strings.xml). See https://developers.facebook.com/docs/reference/android/3.0/Session#APPLICATION_ID_PROPERTY
In your AndroidManifest.xml, you need to add:
... other activity stuff here ...
And then add app_id as a string in your string.xml.