I just bought the crazy app for my iPhone by Brian Eno and
Peter Chilvers called Bloom.
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It creates, or allows you to create, ambient type music on your iPhone or iPod touch. It's well thought out and a blast to mess with. It's nice to see people creating instruments for a platform which don't attempt to emulate "real world" instruments.
Hit the iTunes store to learn more. Only $3.99.
Tape Op is a bi-monthly magazine devoted to the art of record making.