Secret Base Design, makers of the MIDIMorphosis and Apollo over Bluetooth apps, has just released a new music-making iOS app, Double Decker, which turns the user’s Bluetooth keyboard (or iPad keyboard) into a MIDI controller.

In the Double Decker app, the middle two rows of the keyboard (the “asdf” row and the “qwerty” row) are arranged like a piano keyboard. The bottom row of keys uses a different synthesizer patch; the top (number) row triggers drum patches, with the option to add more drum sets using Soundfonts. The user can also send MIDI notes to apps (like SunRizer) running in the background. There are also four different 4×4 grids for triggering samples.

Double Decker supports Soundfonts, and also has full support for MIDI. Using the MIDI Learn feature in apps such as Loopy and Genome, you can start and stop recording, play synthesizers, and switch tracks, all with a Bluetooth keyboard.

If you have multiple iOS devices, you can link them together using the low latency connection provided by Apollo MIDI over Bluetooth. Run Double Decker in the foreground on one device to catch keystrokes, and then send MIDI to a second device, which can have a synthesizer or sequencer app in the foreground.

Double Decker key features:

• Innovative use of an external keyboard to trigger notes.
• Keyboard arranged into two groups, each with four different playing regions.
• Each region can be assigned a Soundfont patch, a set of MIDI destinations, or both.
• Soundfonts can be added using “open in” or iTunes file sharing.
• Each key in each region is configurable as either a note or a chord, with independent velocity control.
• Key configurations can be saved as presets, shared through email, or downloaded from the web.
• The app supports the Audiobus “input” slot.
• Built-in support as a Apollo MIDI over Bluetooth “A” endpoint.

Pricing and Availability. Double Decker is available through the Apple App Store at an introductory price of $1.99.* App requires iOS 6.0 or later. Compatible with iPhone, iPad, and iPod touch. This app is optimized for iPhone 5. For more information about Double Decker, go to the Secret Base Design website.

*Secret Base Design has also put many of their other apps on sale, to celebrate the release of Double Decker.