n-Track Studio – a multi-track audio recorder for iPhone and iPad – has been updated, adding AudioBus support and more.

Here’s what’s new in n-Track Studio 2.1:

• Support for Audiobus – you can now send audio from other apps to n-Track, play your favorite instrument app and record the output inside n-Track alongside the device mic/line input.
• Each Audiobus app can be recorded to a separate track.
• Option to record/process audio when the app is in the background.
• Support for AudioCopy and AudioPaste: transfer audio files between compatible apps

n-Track Studio Multitrack Recorder is available for $5.99 in the App Store.