iOS Musician Apps (210) Instrument Sounds is Keyboards

This is a very simple yet powerful iOS app that performs as a polyphonic audio synthesizer.

Flynth is a synthesizer by Fingerlab, designed for musicality and easy use.

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

Grand Piano for iPad and iPhone.

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

Play with the sound of a full cathedral organ, created by award-winning sound designer Kurt Ader.

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

Pure Piano is a professional, multi-sampled concert grand piano with a unique Morph Pad that allows you to explore a multitude of sounds ranging from mellow and intimate tones to surreal, cinematic textures.

LayR is a polyphonic, multi-timbral synthesizer for iPad and iPhone, delivering up to 256 voices of rich, multi-layered and textured sounds.

Poison-202 is a professional Vintage Midi Synthesizer.

Synclavier Go! is an authentic re-creation of the Synclavier® II Digital Synthesizer of 1980.

VOSIS is a synthesizer that uses scanned synthesis of greyscale image pixel data from photos or live video input. It is also a tool for image audification/sonification and visual music performance.

Galileo Organ 2 is a tonewheel and transistor organ app.

Yonac’s flagship Magellan Synthesizer 2 is a new alchemy of pristine sounds, innovative features, and devotion to user friendliness — all the same preserving the wicked soul of the original.

Kauldron is a synth with new modeling technology, combined with features help you create aggressive synth sounds full of rich analog textures with the fewest knob tweaks.

Harness the enormous power of 8 polyphonic synths: meet KASPAR Supersynthesizer.

Each of the 2 oscillators offers a selection of 5 waveforms: sawtooth and pulse waves are here, along with noise, triple saw and triple FM waves. There's also an additional sub-oscillator strapped into the master section for added oomph.

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

7Xwave - a 7 track sample sequencer with synthesizer & animatable modulation features.

FM TiNES is an electric piano library dedicated to the most beautiful FM electric pianos ever made.