A Tasty Pixel have updated both Loopy (iPhone) and Loopy HD (Universal). Among the changes are an entirely new audio engine, sporting even lower latency, and support for multi-channel interfaces.
• Multi channel audio interface support
• Big improvements in punch in/out interaction and track gestures
• Count-in quantize length setting
• Toggle track sync via MIDI
• SoundCloud update
• Many assorted interface and workflow improvements
Loopy HD also has Retina graphics for iPad 3. The Track Sync toggle via MIDI is for switching on/off the internal sync while recording, with something like a foot pedal, for easy recording off irregular-length tracks.
There is even a new tutorial video from developer Michael Tyson (no relation).