Music App Foundations
Sampler
Numerous music apps utilize a sampler for their foundation. At its core, a sampler simply maps audio recordings to keys. In addition to emulating traditional melodic instruments, a sampler is also useful for triggering percussive or phrase based recordings as well.
Sequencer
A sequencer arranges and plays notes. When used with drum samples, it becomes a drum machine. When used with a pitched instrument, it becomes a groove machine.
Looper
Somewhere in between an instrument and a production tool lies the looper. Audio recordings are loaded, synchronized, and triggered to let anyone remix and compose rich pieces. Useful not only for composition, but also a platform to interactively engage in layered music.