I believe to pull the switch down 4 times means to do it consecutively without stopping. On PC we just use the mouse to drag the switch up and down 4 times. But on iPad, the only way to make the switch move is by tapping at it. And each time I tapped on it, the robot only moves the switch once and then stand by. I try to tap on the switch with very high frequency. But the robot would only do once -> standby -> do once -> standby, never continuously.
But even on the PC version, you can't pull the switch down continuously without stopping; you have to wait a little bit first...not quite to where the vacuum stops, I agree, but I'm finding that you do have to wait a couple seconds before being able to pull the lever again.
On the iPad, yes, you have to wait until the vacuum fully stops first before you can pull the handle again. But still, the time difference between the two versions is, IMHO, negligible.