King of FM: DX Synth/E Piano 4+

#1 DX7 Sounds & Electric Piano

AudioKit Pro

Designed for iPad

    • 4.9 • 495 Ratings
    • Free



FREE Forever! A gift from Analog Matthew Fecher to the iOS Music community. Thank you, so much :)

Classic & new presets, inspired by retro 80s FM Synthesizers used on countless hits! It's like getting a DX7 & SY77 in the palm of your hand.
This is a Premium app: No ads. No subscriptions.
Full app, Everything is included!


This app contains AnalogMatthew's exclusive “Holy Grail” DX7 samples used by Herbie Hancock in the studio. Plus, this app is used by producers for Sting, Jay-Z, Alicia Keys, John Legend, and more!

"Dope! It's in my bag for every session" - Henny tha Bizness, Grammy-winning Producer
“Sounds authentically like the original hardware” – Electronic Musician magazine
"Proves the iPad can be a great sounding, viable synth.” –

"KING OF FM is possibly the BEST FREE iOS MUSIC APP, EVER!" - The GarageBand Guide

PROFESSIONAL! This app can be used as a live instrument controlled with a MIDI Keyboard.
EXPRESSIVE! The main "E Piano" and "Full Tines" sounds have 20+ layers for maximum expressiveness.
Playing live with keyboard supports MIDI Mod Wheel, Pitch Wheel, Program Change, Velocity sensitive sounds, and Sustain Pedal support – All included!

“This app filled my eyes with tears when I first played through the sounds. It brought back memories of my youth, I was transported to a time when anything and everything was possible.” - A grateful musician


• Standalone iPhone/iPad app & iOS AUv3 Plugin

• Over 300+ Presets and over 10,000+ individual samples to inspire you

• FX: Phaser, Chorus, Reverb, Ping-pong delay, Crush, Stereo Fatten, and more!

• Compact! Over 2+ gigabytes of sounds compressed to under 400 mb

• Audio recording: Record your sounds then export wav files! No other apps needed

• Use as an iOS Plug-in in hosts like GarageBand, AUM, Cubasis, Beatmaker 3, and more

• Run on your silicon Mac (Standalone version)

• Includes full lifetime license for both iPhone, iPad, and Silicon Mac

*** We are all volunteers, we do not get paid anything to make this app. We would be humbled if you checked it out. 100% of any proceeds from other apps go to support the AudioKit open-source project ***

Make some music, and share it. Tag us. We want to hear YOU!


KING OF FM is the reboot of FM Player. For the first time, these award-winning sounds are available for iPhone & Silicon Mac. It’s no longer the sound of the past. These sounds are being used on hit records now. This app is the sound of TODAY!

** This app has no official affiliation with Yamaha or the DX7, DX7II, or SY77.
KING OF FM is a free project to bring the joy of music-making to the world. We appreciate Yamaha's beautiful instruments.

** This app has no official endorsement with any artist or producer named in the description (including Herbie Hancock, Jay-Z, Drake, etc). We are humbled they have used our apps. They have received no payment or otherwise compensation for using our apps. :)

What’s New

Version 1.6

Thanks Everyone!
** NEW: Expressive Keys bank – Beautiful & Emotional versions of the original DX7 E Piano & DX7II Full Tines.
Uses a new algorithm for an expressive full 20+ layers of velocity, for the most REALISTIC playing experience ever
Best with a MIDI Keyboard. All this, without adding any additional storage space!!!
** Plus, other fixes and enhancements
Your friend, – Analog Matthew

Ratings and Reviews

4.9 out of 5
495 Ratings

495 Ratings

A. Uzi ,

Update firmware please

Glitch or bug in program where I’m unable to sync other applicators towards keyboard synthesizer. Before I had no issues in sharing applications simultaneously to create unique vibes or even samples. Crashes upon activation of program, not sure if program is equipped to work with other applicators or just only meant for specific ones when it comes to content creations. Aside from that it has been a great tool and add on for on-the-go use or just simply working from home. The extensive amount of features are overwhelming but in a good way. Many viable options that would suite your needs and make your creations even much more unique. Perfect for all sorts from protégés to advance professionals. Hope new sounds would be introduced in the near future.

Nettle Creek 68 ,

I feel like I’m back in the 80’s!!! Amazing!!!

When I heard that this app was being released, I had very high hopes for it. This app/synth did NOT disappoint. I’ve been working with it, for about two hours, and I’m hearing all of the sounds that I grew up with. (I was a teen, in the 80’s, and this was my music!) For instance, the preset “DX Bass 1’ is the exact bass, used for the song “Danger Zone”. As soon as you hear it, you’ll instantly recognize it. There’s just so many iconic sounds!!! If you’ve ever wanted a DX7, like I have, and didn’t want to pay collector’s prices for one… Now, you can!!!

You may be asking yourself, “How can an app, this true to the synths, that it’s trying to emulate, be free?” Because of the immense generosity of Analog Matthew. If you enjoy this app, please review it, and leave him some kind words!

aygkivdkh44444;,.! ,

about the King of FM app

I'm 71 years old and still own an original Yamaha DX7 which I occasionally use as a sound module with my MOXF8. I have installed this app on my iPad, connected it to my MOXF with a Roland UM-ONE, ran the Ipad 4 audio out back into the MOXF A/D in (using the MOXF's built-in effects routed to the A/D in), and disabled FM KING's effects (which slow midi response slightly) and now have a great Ipad sound module for layering the classic FM tines sound with my piano for live performance and recording.
Now to figure out how to disable midi program changes . .
Great Job Audiokit and King of FM!

App Privacy

The developer, AudioKit Pro, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More

More By This Developer

You Might Also Like

Animoog Z Synthesizer
BLEASS Monolit
Numa Player
AUM - Audio Mixer
DRC - Polyphonic Synthesizer
DrumComputer - Synthetic Beats