# KeyStage — Master Instrument Controller

> Master MIDI controller, AUv3 host, and audio mixer for keyboardists. (iPhone/iPad app by Ali Gokturk.)

- Source: https://appshunter.io/ios/app/keystage/id1406132634 (this page in markdown: same URL + `.md`)
- Developer: [Ali Gokturk](https://appshunter.io/developer/1406132633)
- Category: Music, Productivity
- Price: $29.99 with in-app purchases
- Rating: 4.70/5 from 37 App Store ratings · 67 written reviews indexed
- Age rating: 4+
- Requires: iOS 13.0 · 61 MB
- Languages: American English
- Released: 2018-10-18
- Data updated: 2026-07-04
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/keystage/id1406132634/reviews.md

## What is KeyStage?

TRY THE FREE LITE VERSION:

https://apps.apple.com/us/app/keystage-lite/id1437899019

KeyStage is a master controller, AUv3 host, and audio mixer app designed mainly for keyboard players. With KeyStage, you can simultaneously control any number of hardware and software instruments using any number of MIDI controllers in an organized way.

Each project consists of sections (which corresponds to sections of a song). In each section you can change sounds and sound parameters of connected instruments, create complex splits and layers of your keyboard(s), change the functionalities of sliders/knobs/pedals of your MIDI controllers by creating advanced MIDI mappings, write your own scripts, view PDF and JPG files (e.g. sheet music) and lyrics, and much more. 

LIST OF FEATURES

• Connect any number of MIDI controller to any number of MIDI instruments by creating tracks.
• Load AUv3 instruments, effects, and MIDI Processors.
• Assign any region of your keyboard(s) to any connected instrument.
• Change velocity curve and velocity limits, and create velocity splits and layers.
• Transpose notes and restrict notes to any key using pitch shifter.
• Create mixer units to combine audio signals, turning KeyStage into an audio mixer.
• With the player units, you can play wav, mp3, and m4a files, add marker points, automate actions (like play, stop, move to a marker etc.) using custom translators, or trigger certain events (like changing sections) when the player reaches a certain marker.
• Input units allows you to use the microphone input, or the hardware inputs of a connected audio interface.
• The Main Mixer view allows you to control volume levels and pans of all tracks, connect effect units, and connect units to mixer units.
• Create instrument presets to easily change sounds of instruments by choosing patch names from patch lists.
• KeyStage can also import Cubase Patch Scripts to automatically create instrument presets for your MIDI instruments.
• KeyStage automatically detects new MIDI connections and recommends matching instrument presets from a database.
• Simulate auto-sustain on any connected instrument.
• KeyStage has a multi-track recorder, which lets you record any number of tracks simultaneously.
• Change or filter any MIDI signal using custom translators. Use “Relative Control” switch to smoothly change the parameters of your instruments without any jumps.
• Use XY control unit to send control change and pitch bend messages to any connected MIDI instrument.
• Create setlists, quick access all the songs in a setlist from a setlist bar, move to previous/next songs from live console or using external MIDI.
• Create virtual MIDI inputs/outputs for KeyStage. 
• Use virtual MIDI piano controller to play connected instruments.
• View PDF and JPG files. Link any page or region of any file to any section.
• Backup and restore your songs and global properties to Dropbox.
• Map special actions (like changing octaves, switching sections, changing pages of a PDF file) to notes and controllers using custom translators.
• You can write your own scripts in custom translators, which opens up endless possibilities.
• Use MPE routing to control any MIDI instrument using MPE controllers like Seaboard. Use custom translators to change the functionalities of each MPE dimension.
• KeyStage supports smooth transitions between sections. Pressed notes will continue to sound when you switch sections.


You can access demo videos and video tutorials on my Youtube channel.

## Key features

- Connect multiple MIDI controllers to instruments
- Load AUv3 instruments, effects, and MIDI processors
- Create complex keyboard splits and layers
- Advanced MIDI mapping and scripting
- Audio mixer with volume and pan control
- Play and automate audio files
- View PDF and JPG files

## Pricing and in-app purchases

Base price: $29.99.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Instrument Units | Free | one-time |
| Effect Units | Free | one-time |
| Player, Input, and Mixer Units | Free | one-time |
| MIDI Units | Free | one-time |
| Small Tip | $0.99 | one-time |
| Medium Tip | $3.99 | one-time |
| Large Tip | $9.99 | one-time |


## Recent user reviews (10 of 67)

All indexed reviews: https://appshunter.io/ios/app/keystage/id1406132634/reviews.md

### 5/5 — Amazing

*2026-01-23, version 2.2.3*

I’ve never used MainStage nor do I need to because KeyStage does everything I need.

### 5/5 — The best Midi controller app out there

*2025-09-18, version 2.2.3*

A must have for keyboard players

### 5/5 — An Absolutely Fantastic Dream App 🏆

*2025-09-11, version 2.2.3*

I only purchased KeyStage a couple of days ago thanks to a recommendation from a good friend.  This app is more than just Brilliant, it is everything a live keyboard player needs, especially for seamlessly changing Sections (tracks) using MIDI control without loss of any audio, it is pure Wizardry, you have to buy it to find out and then the magic happens ⭐️⭐️⭐️⭐️⭐️⭐️⭐️⭐️⭐️⭐️

### 2/5 — Beautiful app but with a big problem for me

*2025-08-11, version 2.2.3*

Keystage is a beautiful app but is seems not able to download the Custom Translators Database; it reamains locked on “Downloading Translators” without downloading anything. Why?

### 5/5 — Top of the top

*2025-06-19, version 2.2.3*

Ho provato tutto quello che il mercato offre. In questo software trovo tutto quello che mi serve. Potentissimo ma al contempo facile e intuitivo. Spero venga costantemente aggiornato.

### 4/5 — Great tool for live keyboard players

*2025-06-05, version 2.2.3*

I’m quite new to midi and IOS software and until this year only ever gigged with my one keyboard and its onboard sounds. I initially only used Key Stage as a hub to store and manage the live setlists and sounds of my Yamaha YC keyboard. The app makes it easy to call up the next song’s settings as well as the PDF file with my chords and lyrics. I can also arrange the sounds within each song in order and seamless jump from to the next sound with a Bluetooth footswitch. These two simple things alone have considerably reduced my onstage stress.   I have since started enriching the onboard sounds by using Key Stage to mix in other sounds from AuV3 apps on my Ipad. This has been a gamechanger for me and I am only scratching the surface of its possibilities
I have not tried competitor products, so cannot compare. However, the Key Stage user interface is reasonably intuitive and flexible, and the developer has put a lot of thought into the different needs of keyboard-players. As a newbie to MIDI, I found integrating Key Stage with different Auv3 apps took some time to figure out. A more complete user manual with a troubleshooting guide and a beginner’s explanation of MIDI and AuV3 would have helped. However, the developer responded quickly to my questions. More experienced MIDI and IOS musicians will probably manage fine.
Overall, I’m very happy with Key Stage and I can recommend this app to any keyboard players wishing to integrate new sounds into their arsenal without the considerable cost of upgrading keyboards.

### 5/5 — Best app ever

*2025-05-30, version 2.2.3*

Perfect for true musician

### 5/5 — Inspiring!

*2025-04-19*

Logical, flexible, full featured, inspiring!  Thank you for making such a marvelous app that helps us organize the numerous iPad sounds in a logical way helping us to be productive and inspired!  Lately I’ve even experienced quite the benefit from the PDF sheet music feature since I have turned my iPad to portrait mode, so I can view my fairly complicated charts one full page at a time.  I practice more because of the great organization!

### 5/5 — The best iPad app for live music performance!

*2025-01-26, version 2.2.3*

This app is amazing and keeps getting better because the developer is the most responsive I have ever encountered. This is like MainStage for your iPad. In some ways it is even more powerful. If you are wanting to use your iPad for live keyboards, this is by far the best!

### 5/5 — Incredible

*2024-12-20, version 2.2.3*

Been using this on gigs 2+ times a week for the past year and the more I use it, the more I realise how powerful it is. It’s my main keyboard plugin host now, but I use it with keys/guitar setup, and adding in midi pad controllers and even a theremin. Ali is a great developer and responds quickly to questions/suggestions, also a great community of users on Facebook helping each other out. Couldn’t recommend more!

## Frequently asked questions about KeyStage

### What does KeyStage do?

KeyStage functions as a master controller, AUv3 host, and audio mixer primarily for keyboard players. It enables you to simultaneously control numerous hardware and software instruments using multiple MIDI controllers in an organized project-based system.

### What are the key features of KeyStage?

KeyStage allows you to connect multiple MIDI controllers to instruments, load AUv3 instruments and effects, create complex keyboard splits and layers, and perform advanced MIDI mapping and scripting. It also includes an audio mixer, an audio player for various file formats, and the ability to view PDF and JPG files.

### Is KeyStage free to use?

The application offers a free Lite version for users to try. The full functionality is available through in-app purchases, indicating a freemium or free with in-app purchases monetization model.

### What kind of devices is KeyStage compatible with?

While the description doesn't explicitly state device compatibility, it mentions AUv3 support, which is an Apple audio effect standard. This suggests compatibility with iOS and iPadOS devices that support AUv3 plugins.

### How can KeyStage be used in live performance?

KeyStage is designed for live performance by allowing keyboardists to manage multiple instruments and sounds seamlessly. Features like setlists, quick song access, and external MIDI control enable smooth transitions between songs and sound changes during a performance.

## Version history (last 5 releases)

### 2.2.3 — 2024-06-27

Bug Fixes.

### 2.2.2 — 2024-06-15

Small bug fixes.

### 2.2.1 — 2024-06-14

Bug Fixes:



• There was a migration issue from ver 2.1 to ver 2.2, which might result in crashes on some song files. This is fixed.
• The issue of not properly storing full states on tracks (for certain audio units) is resolved.


• "Backing All Data” function for Dropbox was broken. It is fixed.
• Instrument preset suggestions were not being properly stored, and because of that KeyStage was suggesting the same presets for the same MIDI connections over and over again, even if the user cancels. This is fixed.

### 2.2 — 2024-06-12

New Features:

• Major performance improvement: A new option that allows KeyStage to automatically suspend inactive instrument units, which greatly decreases DSP load.
• Seamless transition function is added, which creates two copies of audio units and automatically alternates between them. The above performance improvement also applies to these copies: inactive copies becomes idle.
• Certain audio units causes a spike in DSP (and thus causes a glitch) while changing full states. A new option to temporarly pause rendering of an audio unit while its changing full states is added to prevent such glitches.
• Several new features related to player units: transpose and speed adjustments, Bars+Beats mode with snap option, syncing with global tempo, selective sync between player units, etc.
• “Player units with no parts on the active section are muted” option is added. With this option on, player units behave similar to instrument units, they are muted if there is no corresponding part on the active section. The same option is also added for Input Units.
• The scripting language is reworked from the ground up. Lot of new features, including variable declarations, new variable types (current types are int, bool, float, string, track, part, section, playerUnit, and their array versions), properties of variables, a new smart auto-complete feature, a new log system with custom text, etc.
• Current time is now displayed on the bottom right corner.
• The four in-app purchases, which unlocks differnent types of units, are removed. All units will be available for all new and existing users (even if they did not purchase any of the IAP’s in the past).
• Added a Tip Jar for those who'd like to support future development.

Improvements:

• When you load a new song, KeyStage now loads all audio unit plugins simultaneously, which greatly reduces total loading time.
• When you start KeyStage, it’ll automatically load the last song and the setlist.
• Users can now create nested folders inside "Audio Files" and “PDF and JPG Files” folders. Browsing through these nested folders in player units and in the live console is greatly improved, with the ability to search all files in all subfolders in any folder.
• Song Properties has a new look, similar to preferences.
• Timing issues related to player units are resolved. All operations like looping, moving between markers, are sample accurate and has no latency. 
• New input and output options are added to custom translators related to transport controls and player units.
• New flash option for metronome is added.

Bug Fixes:



• The issue related to changing song via external MIDI signals is resolved.
• In iOS16.x and above, player units may have audio dropouts if where are several audio units and/or player units. This issue is fixed.



• In iOS17.x and above, the time tempo/time signatore view could not be opened. This is fixed.
• While creating a full backup file, all existing full backup files we also added to the new backup file. This is fixed.


• Some issues related to moving/coping files are resolved.
• Several additional improvements and bug fixes.

Known Issues

• If an audio unit gets invalidated while KeyStage is loading a song, it might cause KeyStage to crash. The crash happens before the audio unit notifies KeyStage about its invalidation.
• If the connected audio interface becomes disconnected, KeyStage asks the user to reset the audio engine. Under certain conditions (which I’m still working on to identify), KeyStage may crash during reseting its audio engine and rewiring the connections.
• If two or more keyboards are connected, there is a small possibility of MIDI signal leakage between the two inputs. This only happens (and very rarely) if note signals are send from one keyboard and simultaneously CC signals are send from the other.

### 2.1 — 2023-04-04

New Features:

• Sends. Each non-mixer track can now send a percentage of its output audio signal to mixers.
• MIDI Learn directly from audio units UI, and new parameter handling. AU Parameters can be automatically added to the parameters list by simply tweaking from the UI.
• An advanced MIDI monitoring system, which can simultaneously monitor inputs and outputs of multiple items (tracks, parts, custom translators, MIDI aliases, and audio units).
• The signal levels in the mixer and on the tracks now show the true decibel levels, with a peak indicator. Also the volume levels can now exceed 0 Db.
• In the song properties, users can now configure dynamic and non-dynamic properties (properties that changes from section to section). 
 • The song volume can now be a dynamic property.
• Multi Translators.
• Scripts in Custom Translators. Users can now write their own codes to program custom translators, which opens up endless possibilities.
• Groups of translators can now be saved as “translators chains”, which can later be recalled anywhere.
• Custom and Multi translators can now be added directly to Audio Units.
• Users can now access a new and expanding database of custom translators and chains of translators.
• KeyStage keeps track of the last 10 songs that were loaded, which can be easily
accessed from the Files menu.
• Player Unit’s timelines can now be synced.
• Audio Unit presets can now be changed with program change and bank select messages.
• A new option to automatically load invalidated audio units. These audio units load in the background and does not interfere with other audio units and MIDI signals, so will not interrupt the live performance.
• The font size of lyrics can now be adjusted with a slider.
• Solo function is added to tracks. Also global mute and solo control buttons are added to the bottom bar.
• Battery level indicator is added to the bottom bar.
• “Low refresh rate mode for audio signals” is added to improve the performance of low-end iPads. Further performance options are on the way.
• Users can now create full backup files, which allows them to store and share their whole setup.
• User’s Manual. 
• Info buttons on several different parts of KeyStage, which automatically opens the related section in the User’s Manual.

Improvements:

• Live consoles layout is slightly changed. So now the bottom bar is visible while the live console is on, which allows users to access transport controls, tempo/time signature/metronome controls, MIDI monitor, global solo/mute buttons, battery meter, and DSP meter.
• Several other UI changes and improvements.
• Volume,Pan, and Sends are now considered as track parameters. CC assignments on these parameters are stored on the track rather than the audio unit.
• Audio Unit Parameter values are now visible in the parameters section.
• 'Disable All Parameters' button in the parameters section allows users to disable all parameters.

• Major performance improvements in MIDI routing.
• Deleting an item from a list can now be done with the standard left swipe gesture.
• In the MIDI Learn view, the users can now manually select the CC value.

Bug Fixes:

• Possible crash when loading songs in iPadOS 1.48 and above is now fixed.
• Hanging/overlapping tracks/parts/sections, while copying them is fixed.
• Spikes in the DSP meter when changing sections are now resolved (this was a virtual bug, there was not an actual spike in the DSP).
• Several bug fixes involving Midi Processor Units.
• The problem with player units stopping in the middle of an audio file with a different sample rate is now fixed.
• There was an issue related to controlling volume and pan of input, player, and mixer units via  MIDI. This is fixed.
• Lots of additional minor tweaks and fixes.

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## More apps by Ali Gokturk

- [KeyStage Lite](https://appshunter.io/ios/app/keystage-lite/id1437899019)

All apps by Ali Gokturk: https://appshunter.io/developer/1406132633

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-07-04.*