The app is free to download and includes all functionality and 1 free instrument. You can get additional instruments by liking us on Facebook and tweeting, or through in-app purchases
I would like to recommend it to my fellow electronic musicians, but with such restrictions it is literally not worth the time. Make a lite version that presents the interface and 2 or 3 instruments simultaneously, and a premium one that just unlocks everything. There's a huge variety of electronic music software on the iPad, and musicians don't have the patience to be nickel-and-dimed.