Mellotronics M3000 developer Omenie Limited released St Just in Roseland Organ. This is a wavetable synth designed to faithfully recreate the organ found at St. Just in Roseland church. It is unclear what, if any, inter-app connectivity is available, but it definitely supports hardware MIDI input.
Update: Reader Laarz commented here with a note that the app supports IAA and Audiobus!
St Just in Roseland Organ iTunes Description:This is an accurate reproduction of the organ in St. Just in Roseland church, Cornwall.
The original organ features 2 manuals and a 32-note pedalboard, 22 stops, a rich selection of couplers and a tremulant on the Swell division. The full complement of stops, couplers and tremulant is in place in this digital recreation. Additionally 8 programmable pistons are provided to allow one-touch access to frequently-used registrations. A high quality reverberation engine is provided in the app, and the reverb controls, overall instrument volume, swell, crescendo and the pistons may all be controlled by an attached MIDI controller.
By exploiting Wavetable Trajectory Synthesis rather than sample replay, this app is tiny, yet manages to capture all the beauty and the subtle nuances of the organ.
Note that this version of the app does not contain a playable on-screen keyboard, so attached USB MIDI controllers are required to play the organ.
Privacy Statement : this app does not access any of the personal data on your device.
YouTuber Mark Ireland provides an excellent sounding demo of the new app.