Two axes of
expression.
One thumb.
Treadle turns your iPhone into a fluid MIDI expression controller — slide for expression, glide for vibrato. Built for SWAM and any MIDI instrument.
one-time $4.99no subscription
Expressive playing needs continuous control. Hardware pedals are clunky and tethered. Treadle puts smooth, two-dimensional expression under your thumb — no rack, no cable, no compromise.
Two independent axes
Vertical drag sends continuous expression on CC 11. Horizontal glide adds vibrato or mod on CC 1 — both at once, both fluid.
Tune it to your playing
Set per-axis min/max range and pick a response curve — linear, eased, or steep — so the throw matches your touch and your instrument.
Connects to everything
Bluetooth MIDI, USB, and network MIDI. Treadle also appears as a virtual MIDI source, so any other app on your device can listen in.
Playing in three moves.
Connect a destination
Pick your instrument over Bluetooth, USB, or network MIDI — or send to another app on the same device.
Set your CC & channel
Keep the SWAM-ready defaults or assign each axis its own controller, range, and curve. A two-finger tap or the gear opens settings.
Drag to play
Thumb up and down for expression, left and right for vibrato. Real-time, continuous, hands-on — exactly like a fader you can feel.
A closer look
on iPhone
