Flabbergasting! That is the only word we can use to describe how astonishing KORG iMS-20 truly is. As a steady stream of iPad apps drifts past our field of view we are often amazed and surprised, but only occasionally are we flabbergasted.

KORG iMS-20 is a complete recreation of the KORG MS-20 analogue synth. It contains just about everything you need to create impressive tunes; sequencer, drum machine, mixer and pads, it's all here. Sharing your iMS-20 music could not be easier with the app's near perfect implementation of the SoundCloud network.

For those not entirely up to speed on analogue synths, the original Korg MS-20 has been used extensively by artists such as The Prodigy, William Orbit, Portishead, Jean-Michel Jarre and Daft Punk. Make no mistake, this is a serious piece of music making code and its arrival on the iPad is a watershed moment for iPad creativity. At its introductory price of just £9.49 (under $20) it's also a bargain.

As I write this the KORG iMS-20 app holds the number one spot on both the US and UK 'Paid Apps' charts, eclipsing Angry Birds, Cut the Rope and even Apple's own Pages. Clearly quality is rewarded on the App Store.

KORG iMS-20 isn't for everyone, but if you have any kind of interest in making music with your iPad you need this app, there is nothing quite like it on the iPad or on any other platform for that matter.

YouTube video demonstration by Bullerbyne.