This app makes the famous Jeux dorgues 2 sample set of Joseph Basquin (see http://www.jeuxdorgues.com ) available for playing with MIDI keyboards and a MIDI pedal connected to your iOS or macOS device.
For more information about the app and the underlying Napo framework, please visit the support page http://polaron.de/Jeuxdorgues/ , the Napo documentation at http://polaron.de/Napo/ and in particular the user manual at http://polaron.de/Napo/manual .