works its way through a typical ear-training syllabus, but instead of clicking with a mouse, you provide your answers by playing back the intervals or phrases on your instrument. This builds a strong connection between your hearing (internal or external) and your hands. Ideas flow straight in and straight out.
Ear training in this way means that you can learn to recognise much more diverse ideas. Using a mouse, working with phrases anything longer than a couple of notes becomes very clunky. On your instrument though, learning to recognise longer phrases by ear becomes realistic.
It is also a great help for students learning scales, when they are unsure of what the scale sounds like. The software plays the scale, and the student plays it back. This saves students from practicing scales incorrectly, simply because they didn't realise they were playing the wrong notes.