It’s all in the name. StepPolyArp Unit is an app for iOS that does real-time polyphonic and polyrhythmic MIDI step arpeggiation and sequencing. This could be very handy.
As an arpeggiator it can create melodies and patterns based upon played notes or chords. Or as a sequencer you don’t need to play anything, you can simply enter 1-32 notes and off you go. But that’s just the beginning. You can build in event controllers, transposition, polyrhythmic step controllers all driving the arpeggiator engine.
A single preset can contain 16 patterns, 5 polyrhythmic step controllers and a 32 steps event matrix with 11 polyphonic and polyrhythmic lines. I’m not sure exactly what that means but it sounds like a lot of stuff. The patterns can be chained and switched between on the fly. And you can send the generated notes and rhythms wherever you like. You can run it as a plug-in inside a DAW, you can Audiobus it to other iOS synths, you can send it out to your MIDI hardware or you can use its own internal sound engine. Sync is provided by itself, routed internally from other apps, external or via Ableton Link.
But the features keep coming. There are 6 arp modes, random modes, chord modes, scales and each step can have customisable MIDI control. It’s a wonderfully fully featured step sequencer and arpeggiator that would be a lot of fun to run internally but could also excel at being routed through a MIDI-to-CV converter and into your modular. I always like it when an app does one thing brilliantly rather than being part of a bigger app and StepPolyArp is a great example.
It will cost you an eye-watering iOS price of $14.99 and requires iOS 11 and later.