iOS Musician Apps (115) Supported Technologies is Inter-App Audio (IAA), Instrument Sounds is Keyboards

With EGSY01 you can create sounds, from modern ones to vintage analog ones, working with arpeggiator, step sequencer and FM, addictive and subtractive synthesis.

Shoom is an expressive XY pad synthesizer. Or, more precisely, three identical synthesizers in one app.

The unique dynamic wavetable synthesis allows you to explore an unprecedented wide range of sonic territory.

Xynthesizr is a streamlined yet capable 32-step matrix sequencer/monotimbral synthesizer with generative features and MIDI.

Combine 3 oscillators and a noise envelope to produce bright 80s-style synths, deep rich bass, punchy kicks and snares, a variety of screaming leads, and even breathy percussion.

Tardigrain is a granular synthesizer. Sounds are created by taking smaller fragments of a sample and playing them back in a non linear fashion, with settings for grain size, direction, step size and more.

The Optigan, short for Optical Organ, was a chord organ from the early 1970’s.

The hybrid synthesis algorithm on which Addictive Pro is based provides you with efficient means for easy control of complex sounds far beyond usual sound synthesis methods.

Elsa is a retro style sampling keyboard with tempo based looping.

SynthQ is a subtractive synthesizer with a customizable interface.

SunVox is a small and fast cross-platform modular synthesizer with pattern based sequencer (tracker).

Esoteric Synth is a unusual generator of synthetic sound events. The synthesis is based on 5 oscillators which are intersected through an multiple amplitude modulation and multiple frequency modulation making  an high sound variability. This App is suitable to generate complex sound textures, glitches, noises, sound clouds, sound drones, point sounds and more.

With the special lightweight version of SynthScaper LE you can easily create and modify your own multi-timbral pads and atmospheric soundscapes.

Based on Hohner's iconic Corona Classic diatonic accordion, this virtual accordion app plays in all five of the most popular tones: EAD (Mi), FBbEb (Fa), GCF (Sol), ADG, and BbEbAb.

Electro-Harmonix, a pioneer since 1968 in the field of sound effects pedals for musicians, has produced an app which is a faithful digital re-creation of their circa 1980 analog cult-classic, The MINI-SYNTHESIZER.

Englitina is an authentic-sounding English Treble Concertina for the iPad.

Shape is a polyphonic synthesiser allowing the user to draw the shape of the oscillator waveform.

This intuitive virtual instrument features a super responsive  fingerboard that plays and sounds like the traditional instrument in the most common two-row tunings of B/C, C#/D, and D/G, as well as an extended B/C+ layout with four chromatic buttons on a partial third row.

Combo Organ Model V is a musical keyboard app for iPad/iPhone/iPod touch that simulates the electric transistor organ, is called a Combo Organ. It was a big success in the 1960s.

Mimicking the layout of Hohner's iconic chromatic button accordions (CBA), both B-System (Bayan) and C-System, this intuitive virtual accordion is easy to play and sounds exactly like the real instrument.