QuantiChord is Universal on iOS, and even arrives with an official demo video to show it off!
QuantiChord iTunes Description:"QuantiChord" is a MIDI effect that generates chords from incoming notes and quantizes the results to a pre-defined scale. It can be used as a standalone application or as an Audio Unit MIDI effect plug-in.
The chord is generated by adding up to 8 transposed notes to the original note played. Once the chord is generated, it is quantized to limit it to the selected output scale.
The application supports full internal and external MIDI connections for input and output. An internal sound bank is included.
The Audio Unit MIDI effect plug-in supports multiple instances. A compatible host is required to run the plug-in. The host must support the Audio Unit MIDI effect format.
• Standalone application and Audio Unit MIDI effect plug-in
• 8 transposing sliders from -24 to +24 semi-tones (+/- 2 octaves)
• 1 global transposer slider
• Scale quantizer
• Lockable parameter protection when switching presets
• Resizable keyboard
• Sample-accurate timing
• Internal sound bank
• Receiving MIDI from external MIDI sources
• Internal routing of inputs, outputs
• Send MIDI to a virtual port that can be used as MIDI input by other "Core MIDI" compatible applications
• Random creation of presets
• Presets browser
• Full support of "Split View" and "Slide Over"
Compatible hosts supporting Audio Unit MIDI effect:
Supported MIDI connections:
• Virtual "Core MIDI" connections between applications
• iOS compatible MIDI interfaces
• MIDI over Wifi
An iPad or iPhone with iOS 12 or later
Update: The Sound Test Room did a demo for this over the weekend. Embedded here is the official intro.