MIDI Wrench is a versatile app designed for iPhone that serves as a comprehensive tool for all your MIDI setup needs. It allows you to connect MIDI keyboards, sound expanders, and other MIDI devices to your iPhone using the Apple USB camera adapter or any other compatible adapter supported by Apple.

With MIDI Wrench, you can visualize and monitor MIDI messages sent by your connected MIDI devices, making it easier to identify and troubleshoot any problems in your MIDI setup. Additionally, you can also send MIDI messages to the connected devices, including Note-On, Note-Off, and Control Change messages.

One of the standout features of MIDI Wrench is its virtual MIDI keyboard, buttons, and rotary knobs. These virtual controls are fully configurable, allowing you to assign MIDI controller numbers and customize their functionality. What's more, the on-screen controls automatically update to reflect the values sent by your connected MIDI devices.

The app also offers the ability to filter out MIDI events that you're not interested in, ensuring that you only see the relevant information. Furthermore, MIDI events can be easily copied to the iOS clipboard with a single tap, allowing you to paste them as text in other apps like Mail.

MIDI Wrench is a free app that does not contain any ads or intrusive elements. The developer, Christian Schoenebeck dba Crudebyte, is committed to protecting your privacy and ensuring that none of their apps include any "spy" behaviors. MIDI Wrench does not collect any personal information, and you can learn more about their privacy commitment by reading their "Privacy Policy for Mobile Apps."

With its extensive features and user-friendly interface, MIDI Wrench is an indispensable tool for anyone working with MIDI setups on their iPhone.