This is a great app, but FYI there are a very limited number of phones that record the line audio. Most require it to record through the mic while on speakerphone mode.

Not Supported:

http://www.grinzone-apps.com/1/post/2013/04/not-supported-de...

Tested (doesn't mean supported necessarily):

http://www.grinzone-apps.com/1/post/2013/04/welcome-to-our-b...