I am afraid of knowing android doesn't have a native api to record voice calls. even the streams are abstracted in Operating System and inaccessible in application layer as Emmanuel hase stated. I consider it as a Serious mistake of Android Devs. if a security Wall have one tiny Hole its not secure any more. So even if droid restricts or tries to restricts there exists other phones where one can have such kind of functionality. even a custom droid kernel can have such kind of functionality. This only makes droid Users poor nothing else.
