OrangeAid for iPad gives you a comprehensive Reason controller

I'm not a reason user, so I can't comment on if this is a good tool or not, but it looks like it's got a lot going for it. Here's the app's description:

OrangeAid turns your iPad into a control surface for Reason and Reason Essentials, giving you seamless integration with all your favorite Rack devices. Whether you're tweaking away in search of that new synth lead, making beats, recording or performing OrangeAid is ready to help.

• Create your own layouts to control your Rack devices, song files and play instruments the way you want, all from within the app.
• Parameter mapping is a breeze with OrangeAid. Just browse the built-in lists and tap to map!
• OrangeAid can follow the Master Keyboard input in Reason. Change tracks in the Sequencer and your rack layouts automatically change to match the new device.
• You can also use Reason’s surface locking to stay focused on a specific instrument or effect.
• Handy Transport, Track & Patch controls are always available.
• Super-fine parameter control for Knobs, Sliders & Pitch Wheel.
• Designed to take full advantage of Propellerhead Software's Remote technology for complete, two-way communication with Reason.
• Works alongside your existing hardware MIDI control surfaces & keyboards.
• Connect to Reason using Wi-Fi, MIDI over Bluetooth LE or with a wired connection using class-compliant equipment.

SUPPORTED RACK DEVICES
Instruments

• Redrum Drum Computer
• SubTractor Analog Synthesizer
• ID8 Instrument Device
• Dr. Octo Rex Loop Player
• NN-XT Advanced Sampler

Effects

• Scream 4 Distortion
• RV7000 Advanced Reverb
• Line 6 Guitar Amp
• Line 6 Bass Amp
• MClass Equalizer
• MClass Compressor
• MClass Maximizer
• MClass Stereo Imager
• DDL-1 Digital Delay Line
• CF-101 Chorus/Flanger

Utilities

• Combinator
• Matrix Pattern Sequencer
• Mixer 14:2
• Line Mixer 6:2

Other

• Sequencer
• Transport
• ReGroove Mixer

AVAILABLE WITH THE PRO UPGRADE
Instruments

• Kong Drum Designer
• Thor Polysonic Synthesizer
• Malstrom Graintable Synthesizer
• NN19 Digital Sampler
• External MIDI Instrument

Effects

• Pulveriser Demolition
• The Echo
• Alligator Filter Gate
• BV512 Digital Vocoder
• Neptune Pitch Adjuster
• RV-7 Digital Reverb
• D-11 Foldback Distortion
• ECF-42 Envelope Controlled Filter
• PH-90 Phaser
• UN-16 Unison
• COMP-01 Compressor/Limiter
• PEQ-2 Two Band Parametric EQ

Utilities

• RPG-8 Monophonic Arpeggiator

RACK EXTENSIONS
Support for individual Rack Extensions is available with separate In-App Purchases

• Audiomatic Retro Transformer
• A-List Acoustic Guitarist
• A-List Electric Guitarist - Pop Chords
• A-List Electric Guitarist - Power Chords
• Parsec Spectral Synthesizer
• Polar Dual Pitch Shifter
• Pulsar Dual LFO
• PX7 FM Synthesizer
• Radical Keys
• Radical Piano
• Rotor Rotary Speaker
• Softube Amp
• Softube Bass Amp
• Synchronous Effect Modulator

That’s only the beginning - support for more and more Rack Extensions will be added with regular updates.


WAIT - WHAT ABOUT THE MIXER?
Mixer support is coming soon, and there are many other features in the pipeline. If you have suggestions for new features or ways to improve OrangeAid, please get in touch!
Email: contact@soundzest.com
Twitter: @soundzest
Or you can use the feedback form in the app.

REQUIREMENTS
Compatible with iPad 2 or later and iPad mini or later. Requires iOS 7 or later.

Requires Reason 6.5 or later, or Reason Essentials 1.5 or later, with the accompanying OrangeAid Remote Codec installed (download from http://www.soundzest.com/support/).

Wi-Fi connection to a Windows PC requires 3rd-party software.

MIDI over Bluetooth LE requires a compatible iPad running iOS 8 or later, and a compatible Mac running OS X Yosemite v10.10. or later.

Wired connections require MIDI interfaces that support SysEx.

Visit http://www.soundzest.com/orangeaid/ for more information.

Reason, Reason Essentials and Remote are trademarks of Propellerhead Software AB. References or use of logos or trademarks do not necessarily constitute or imply an endorsement or recommendation by Propellerhead Software.

What's New

• Layout auto-switching. Set OrangeAid to follow Reason’s Master Keyboard input, or use surface locking to control a specific device, and your Rack layouts automatically change to match.
• Layout Quick Picker. Open or add another layout without having to navigate to the Layout Organizer and back again.
• Super-fine parameter control for Knobs, Sliders & Pitch Wheel. While touching a control, move your finger off to the side (or above/below for the Horizontal Slider) to change the parameter value more precisely. The further away you move, the more precise it gets.
• Filter by Parameter. Mountains might be mountains in Zen, but buttons are not always buttons in the Rack. Sometimes they're really switches (yes, I’m looking at you Mr Combinator!) Use ‘Filter by Parameter’ in the controls list to find control types guaranteed to match a particular parameter.
• Bluetooth LE MIDI. If your iPad supports it, you can use Bluetooth LE MIDI to connect to a Mac running OS X Yosemite v10.10. or later.
• Transport, Track & Patch controls always available in the toolbar.
• Someone pointed out there are other colors besides orange. Yes, it’s true! And, as it happens, they’re quite handy for telling your Oscillator 1 from your Oscillator 2.
• Improved syncing between OrangeAid and Reason.
• Added support for devices in the full version of Reason with the OrangeAid Pro Upgrade In-App Purchase.
• Added support for Propellerhead Rack Extensions with individual In-App Purchases.
• iOS 9 compatibility.
• A thousand other little fixes & tweaks that all add up to make things better.

 OrangeAid costs $9.99 on the app store, plus IAPs as described above.