They ruined it. I mean ok, ads are a bit intrusive but you come to expect that in Android games. What they ruined is the gameplay. The old Tetris used to be great but it was discontinued for some time, then this 'official' version appeared and it looks and sounds like the older version but the sensitivity in the game is weird and this makes you keep putting blocks into the wrong places. This happens at crucial times making it really frustrating and unplayable. Uninstalled it.