Rubberband: Microtonal Synth
Maqam, quarter-tone, MPE glide
Only for iPhone
Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.
iPhone
The elastic synth for the world's tunings. Glide — GRAVITY tunes you. Maqam, just blues, 19 and 31-TET, true quarter tones. Now in 11 languages.
RUBBERBAND is not a keyboard. It's an elastic surface where every line is a magnet: you glide, and GRAVITY pulls notes toward the scale. All the way up, you can't play out of tune. At zero, it's free glissando. In between, your ear decides.
A microtonal synth built to be both an instant toy and a serious instrument — played like a theremin or a ribbon controller, tuned like the world.
THE WORLD'S TUNINGS
RUBBERBAND truly speaks microtonality — not an effect, the heart of the instrument. Arabic maqam, Turkish makam, Persian dastgah, just intonation, just blues and barbershop, klezmer modes, Southeast-Asian equiheptatonic, xenharmonic temperaments (19- and 31-TET, the harmonic series), Western scales — with region-adjustable neutral tuning. The engine thinks in cents: any tuning on Earth is within reach.
36 VOICES
Plucked strings, basses, bowed instruments (violin, cello, kamancheh, sarangi), bells and bars, synth voices, the RUBBER↔STRING morph, the instruments of the East (oud, qanun, santur, ney, zurna, duduk), and granular clouds. Every voice is physically modelled and rendered in real time — no samples.
EXPRESSIVE UNDER THE FINGER (MPE)
Pressure is dynamics; gliding along a string changes the colour, from sul tasto to ponticello; vertical is pitch. Tilt the phone and it becomes an axis of expression. MPE MIDI out drives your other synths with the same gestures.
LISTEN TO THE ROOM
RUBBERBAND hears the music around you, detects the key, and tunes to it. Play along with anyone, in tune.
ALSO
A DRONE holding the tonic under your playing, a sympathetic halo that rings the neighbouring strings, a LOOPER to stack loops, and recording your takes straight to your device.
IN YOUR LANGUAGE
Full interface in English, French, Spanish, Italian, Portuguese (Brazil), German, Turkish, Japanese, Simplified Chinese, Korean and Arabic — with real musician vocabulary in each, not machine translation.
Haptics, Metal rendering, fully native. No account, no ads, no data collected — the microphone is analysed locally and never recorded or sent.
FREE, THEN PRO
Start free: the full elastic surface, starter voices, and a taste of the world's tunings. The RUBBERBAND PRO unlock (one-time purchase) opens all 36 voices, the full catalogue of world tunings, recording and sharing, MPE MIDI output, MOTION and LISTEN.
One-time purchase. No subscription.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
LENGTH and RELEASE now reach the bells and the drum heads: each voice's character goes all the way.
New: “I have a code” in PRO, to redeem a promo code.
The developer, Thinkspark, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Thinkspark
- Size
- 1.6 MB
- Category
- Music
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
English and 10 more
- English, Arabic, French, German, Italian, Japanese, Korean, Portuguese, Simplified Chinese, Spanish, Turkish
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- RUBBERBAND PRO $12.99
- Copyright
- © 2026 Thinkspark SRL