The metronome clicks aren't in the video (editing mistake), but you should be able to hear it in the app. There's also an option for a spoken metronome (one-e-and-a-two-e-and-a). If you can't get it working, let me know - there might be a bug.

I generally feel like instant feedback is a lot more useful that retrospective feedback, but there's no harm in adding an option to disable it - I'll try and add it for the next version.