There are two FL Studio Mobile applications:
FL Studio Mobile For iPhone & iPod Touch (inc with Retina display support) - $14.99
FL Studio Mobile HD - Image Line Software For iPad 1 & 2 - $19.99
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You may also be interested in these posts from the blog.
"It's on the roadmap, stop nagging! We have a development team working on a low-latency Android audio-engine and there are many screen resolutions and device specifications to consider, it's not as simple as you may think :)"