Sebastian's interface is streamlined, to help you achieve a learning 'flow' with minimal distraction. The best ear training happens when you engage your muscle memory by using a keyboard and 'feeling' sounds. So you can use a MIDI keyboard with Sebastian, but even if you don't have one, the on-screen keyboard helps you learn to map sound to something tangible.
Unlike some other programs, you don't perform 'drills', with gaps of difficulty between drills and distracting accuracy measurements. Sebastian gives you one problem at a time, progressing as you do, and holding back where you struggle. And it sneaks in review of problems you missed before. Sebastian is designed to take a challenging skill and make it fun for anyone to learn.