Shape is a polyphonic synthesiser allowing the user to draw the shape of the oscillator waveform. The positive side of the oscillator is represented by 32 blocks and the negative side is its mirror, generating all sorts of possible raw retroish sounds. Add effects like arpeggio, stereo delay and a resonant filter and record your sounds on a classic tape. Connect to other apps with audiobus, inter app audio and midi.

+++ 16 voice polyphony.
+++ Shape 2 oscillators with ADSR.
+++ 2 lfo modulation with ADSR (envelope, pitch or duty cycle).
+++ 3 oscillator mixing functions (add, subtract or multiply).
+++ Record on tape with infinite overdubs (save, load, import, export).
+++ Arpeggiator.
+++ Stereo delay.
+++ Resonant filter (low, band and high pass).
+++ Accelerometer parameter controller (Sphero).
+++ Mini linear sequencer with euclidean rhythm.
+++ Save/load synth parameter state.
+++ On screen 25 key stylophone style keyboard.
+++ AudioBus (
+++ Inter app audio.
+++ Ableton link.
+++ CoreMIDI and iaa midi.
+++ Akai synthstation 25 compatible.
+++ MAPI audio copy.
+++ Soundcloud upload.

Support for Akai Pro's SynthStation25 keyboard controller is included. SynthStation25 delivers instant hardware control for improved performance capability and expression. For more information on SynthStation25, visit

What’s New

Version 4.1.6

+++ Minor tweaks to adsr and lfo wave control.

Ratings and Reviews

5.0 out of 5
3 Ratings

3 Ratings

Ben Efitofadoubt ,

Erik The Great does it again!

First class updates to a first class app from a first class developer.
Get them all! What are you waiting for?

SynthyMiranda ,

Awesome Update!!!

I always loved the sound of Shapesynth, but could never wrap my head around the minimal and confusing interface. But this update basically restructures everything--it's virtually a new app. The developer has grown and grown, I think. His more recent apps like Elsa and Strng are brilliant, and I think all that experience has been applied to reinvent Shapsynth! So nothing but mad props from this girl! 😊

JRSIV1975 ,

Erik's update makes it a whole new app

Erik Sigth's apps are some of the most unique iOS music production tools around. They all have a GUI that admittedly one likes or doesn't like most of the time. If there are indicators to what a control does or at least a manual or help (?) option I don't mind the layouts. Thing with the old version of the shapesynth was trying to make patches while using such a bare interface did cause problems. Now that things are labeled and laid out better, the synth is a joy to play.

And a totally unheralded aspect of this synth is the brilliant recorder. For an old analog dude who learned on Tascam PortaStudios there is the joy of seeing the little tape graphic and some of the more tape oriented controls. The real use of the recorder should be explored, most synths get AudioBussed or AUMed out to a DAW like Auria or Cubasis, this recorder can allow you to make some cool experimental soundscapes and then manipulate them further on in a DAW or app like Samplr. Just a great app for under $5 and incredible at just $2.


erik sigth
8.3 MB

Requires iOS 7.0 or later. Compatible with iPhone, iPad, and iPod touch.



Age Rating


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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