The object is to rotate the pips, in their fixed places, so that no steam escapes. I did the first 25 or so levels rapidly while watching the news. I checked the leaderboard and saw only 50 players.
A couple of things are different: see the double pronged gray pipes? That's new. Look at the yellow shapes: those are pipes that must be connected - but you don't know what the opening/closing valves look like.
Big surprise: see the red circles? Tap on them once and that whole square region will rotate. Very interesting.
One negative element: each time you start a new level, the top of the puzzle is obscured by that blue bar with the time. I didn't realize, until level 60, that you're supposed to drag the playing field down. Ugh.