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

Syndt is a polyphonic synthesizer with a lot of possibilities.

Tines emulates an electric piano.

This synthesizer emulates male voice vowels in a unique way.

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.

Phase84 is a phase distortion synthesizer.

Attack Drums is a synthesizer designed mainly for drum sounds, but the powerful sound engine can also be used for everything else - including vocals.

KQ MiniSynth is a polyphonic modular synthesizer.

Just a Toy Synthesizer. Included: 2 Oscillators, LPF, Delay effector, Ribbon controller.

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

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

Pixound provides a deep musical experience that lets you instantly create music using any picture.

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

Pure Synth® Platinum is a full-blown rompler/synthesizer for your iOS device. Neither the synth engine or the sample engine is an afterthought: Both engines are fully capable and feature-rich. The romper section contains a well rounded assortment of analog, synth, string, digital, and acoustic instruments.

Professional Virtual Analogue Synthesizer.

SpringSound is a physical-modeling audio synthesizer that produces sounds by simulating interactions and vibrations of a set of activators and masses connected to springs.

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.

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.

Groove Rider GR-16 is a professional step-sequenced groove box, inspired by professional hardware drum machines and rhythm boxes.

Poison-202 is a professional Vintage Midi Synthesizer.

DRUMLAB brings a new approach to the Drum Machine by allowing you to play with both Samples & Synthesis drum sounds.