It may be the case that - now that it supports Audiobus - GarageBand provides a cheaper and simpler solution for mixing iOS projects. And Steinberg’s Cubasis has an edge in the sense that it deals with MIDI instruments rather than purely audio tracks. But you’ll still be hard-pressed to find a deeper, more fully feature and professional feeling app for mixing and arranging audio than Auria.
The app features channel strip and effects plugins from PSPAudioware, with extra effects and third-party tools available as in-app purchases. It’s 64-bit, can handle multiple different sample rates and can record up to 24 tracks simultaneously via a compatible interface and Apple’s camera connection kit.
Auria supports Audiobus too, meaning that even though it doesn’t support MIDI tracks, it can still be used as a hub for various iOS instruments and effects.
Full review: WaveMachine Labs Auria
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