iOS Musician Apps (128) Supported Technologies is Inter-App Audio (IAA), Instrument Sounds is Keyboards

Dazibao is a polyphonic synthesizer programmed by an innovative interface : you create several tones, then you arrange them on several time lines.

This app reproduces the functionality of Casio’s best-selling CZ-series models, such as the CZ-101 (first released in 1984), and also includes new functions.

Cube Synth is a groundbreaking new software instrument giving you the power and flexibility of additive synthesis together with easy editing and morphing capabilities.

Continua is a three-oscillator / dual-filter six-voice virtual analog synth, with fully polyphonic modulation sources and built-in custom-designed effects, for everything from complex, evolving chill-out soundscapes to New Wave synth stabs.

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.

Colossus Piano sets a new standard in terms of realism, detail and overall quality of piano sounds on your iPad, iPhone and iPod touch.

The second best sounding piano app in the App Store (after "Colossus Piano")!

We painstakingly sampled the sound from every key and button of an authentic 1960’s electric chord organ to bring this timeless instrument to your device.

CHAiOS SYNTH 2 is a synthesizer/melody generator that creates unique melodies with just one tap.

Fed up with standardized presets and instruments? Feel lost in overcomplex filters and effects? Don’t wanna sound like everyone else? BLEASS is just the right instrument for you: it unleashes your inner musical creativity by bringing music production and performance to its very core: play, perform, compose beats and melodies in a new yet intuitive way thanks to its multitrack sequencer, synthesizer and drum machine.

bent.fm is a full FM model of a circuit-bent synthesizer.

Portable Music Production Studio : create beats, compose whole tracks, sample, record, sequence, perform, mix and arrange your own music.

Baervaag brings FM synthesis to the masses! An easy to use but still tweakable synthesizer, accessible to everyone.

AutoPad is an app for musicians that allows you to play ambient pad loops.

AutoArp turns your iPhone (or iPod Touch) into a musical instrument that is halfway between a traditional auto-harp zither and an arpeggiated analogue-style synth.

AudioKit Synth One is a completely free & open-source professional iOS Synthesizer. 

Free iPad instrument featuring the classic sounds of famous 80s FM Synthesizers.

Epic 64-voice Virtual Analog / PCM iPad Synth. Inspired by the Digital Synths of the 80s and 90s.

Arpeggist is a MIDI Note arpeggiator with a very flexible step matrix editor for programming and a unique “rolling dice” random arpeggio generator.

A matrix-controlled arpeggiator designed to play with your thumbs.