MIDI Wrench 4+

MIDI Monitor & MIDI Controller

Christian Schoenebeck d/b/a Crudebyte

    • 4.7 • 62 Ratings
    • Free



The Swiss army knife for your daily MIDI setup tasks. Connect a MIDI keyboard, MIDI sound expander or any other MIDI device to your iPad, iPhone or iPod touch by using the Apple USB camera adapter or any other adapter supported by Apple. Visualize and monitor MIDI messages sent by the connected MIDI device or send MIDI messages to those connected MIDI devices. This is a simple but helpful tool to find problems in your MIDI setup or simply to spot what kind of messages various MIDI devices are sending exactly.

This app supports all hardware and software sources for MIDI, including Bluetooth LE MIDI !

Current Features:

• Lists all CoreMIDI devices (i.e. attached MIDI accessories) and all so called "virtual CoreMIDI ports" (i.e. audio Apps) on your iPad / iPhone / iPod touch.
• Displays incoming MIDI events of external MIDI hardware and local MIDI apps in real-time.
• Send MIDI Note-On, Note-Off and Control Change messages by using the virtual MIDI keyboard, buttons and rotary knobs.
• Virtual on-screen MIDI controls are fully configurable, so you may assign other MIDI controller numbers and more.
• The virtual keyboard keys, rotary knobs and buttons automatically update to the values sent by connected MIDI devices.
• Filter out MIDI events you are not interested in.
• Copy MIDI events with one tap to the iOS clipboard, and paste them as text in another app like Mail.

This app is free, and it does not contain any ads or other annoying things. Really!

Anti-Spy Commitment: We take your privacy very seriously. None of our apps contain so called „spy” behaviors and we committed ourself to a very high privacy standard. MIDI Wrench does not collect any information. For more information about our privacy commitment, read our „Privacy Policy for Mobile Apps”.

What’s New

Version 1.4

This update adds the following new features:

• Support for new iPhone models (e.g. iPhone 11 variants).
• MIDI channel for virtual on-screen MIDI controls is now configurable.
• MIDI events monitor may now be paused (either by new pause button or by long-tap context menu).
• Added optional filter for MIDI RT Clock events.
• Added support for sending MIDI Program Change commands.
• Added support for sending MIDI Real-Time Messages (Start, Stop, Continue, Active Sensing, Reset all Receivers).
• Added support for sending MIDI Note Pressure (Polyphonic Aftertouch).
• Added support for sending MIDI Channel Pressure (Monophonic Aftertouch).
• Added option for forcing the app to continue running in the background (i.e. to capture MIDI data on MIDI events monitor while working with another audio / MIDI app in foreground).
• iPhone: MIDI events monitor may now be cleared by long-tap context menu.

This update also fixes thes following issues:

• Fixes issues with the graphical user interface (iOS 13).
• Fixes graphical issues with some older iPhone models.
• MIDI event monitor: MIDI channel numbers are now displayed starting by 1, as commonly expected in MIDI world (not by 0 as actually on technical level which was apparently confusing for many users).
• Fixed some MIDI SysEx messages not being displayed correctly with certain Bluetooth LE MIDI connections.
• Fixed issue with touch events on lower edge of screen (iOS 11 and higher).

**NOTE**: The previous clear button had been replaced by a pause button. You can find the clear function now from the context menu (popup menu) by long tapping onto the MIDI events monitor.

That's it for now, thanks for your feedback and take care!

Ratings and Reviews

4.7 out of 5
62 Ratings

62 Ratings

GarageBand composer ,

Great app. Great potential

Is it possible to add options like (1) change the range of keys and (2) set the keys to different scales. It will be nice to control a vst on the desktop from the GarageBand with this app or similar set as an auv3 instrument. I am trying to use an iPad as a midi controller for the vst on a pc using Bluetooth midi. Thanks for creating a great simple app but maybe additional options can be sold as in app purchase.

CynicAndMusicLover ,


This app is so fantastic at what it does that I wish it was designed to do just a tad more because then it could really be the MIDI ‘Swiss army knife’ so to speak, not just a “wrench.” If you use your iOS device with any MIDI I/O especially multiple types simultaneously like hardware MIDI I/O via USB or bluetooth/Wi-Fi MIDI, virtual MIDI, various apps simultaneously that use MIDI this app is incredibly valuable because when something isn’t behaving the way you’re expect, getting to see in realtime line-by-line each MIDI command you can quickly figure out what’s actually going on and adjust that to meet goals. There’s a a few knobs (4) which have plenty of versatility in that you can configure them to any MIDI channel or CC desired , its a bit weird to me to see just a bit of that type of functionality - but in a way it makes total sense and I wouldnt’ wish them gone. I was hoping maybe it could work as a MIDI patchbay - it has this one feature which will “echo” all inputs to outputs but it says that’s meant for measuring latency (very cool) but it would only work for MIDI routing in the very specific cases. Great free app.

wkrasl ,

Does what I need

I am using several midi compatible apps on my iPad. Each time I come back to my piano to do something, the first thing I do is power up my piano, turn on Bluetooth on my iPad, and open MIDI Wrench to reset the iPad connection with my piano's MD-BT01 Bluetooth adapter. It works every time. I do see that this app does a lot more, but I don't need any feature other than making the connection.

The only reason I am not giving this five stars is because, if I take a break (20-30 minutes?) without turning off either my Piano or my iPad (and my iPad is set to never auto-lock), I sometimes discover my connection has been disconnected. Then I have to reopen this app (still running in background) and reconnect. As long as this app is still running in the background, it should wake up often enough to keep that connection alive.

App Privacy

The developer, Christian Schoenebeck d/b/a Crudebyte, 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

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