iOS stalwart Retronyms is set to offer a new clip-based performance, mash-up and DJing tool when it releases Hook for iPhone and iPad later this month.
This enables you to arrange and trigger loops on a grid (think Ableton Live's Session view and you're getting close) and transition between tracks/cells on the fly with a 'smart crossfader' known as the Flux Fader. This offers 2-axis control over nine riser synths, glitch and gate effects, tempo-synced filter sweeps, an EQ, beat drop, tape stop, and filter drop.
Sounds can be imported into Hook using AudioCopy or the built-in sampler. You can record via your mic/line in and Inter-App Audio, or grab sounds from iTunes or Spotify. There's also audio transient slicing and waveform editing.
Project tempo changes can be made in real time and all clips (or hooks) are kept in sync. Other features include "a full mixer, tons of tracks, integrated FX bus, per-cell FX, transpose, time stretching, tuning, timing and trigger settings, and more."
Keep an eye on the Retronyms YouTube channel for preview videos in the lead-up to Hook's launch on 21 July.