It’s great, but needs one more adjustment.
My only critique is that the beep could sound a little more ominous than it already is.
To elaborate; the alarm begins at a slow pace and picks up to a medium pace. However, I would like for it to step up once more to a rapid pace (ideally double the tempo of the current fastest pace) after more time has elapsed. If the app could do that, it would earn 5 stars from me.