Switch&Drop starts by asking you to agree to a EULA, this is always a good sign. Otherwise you just can't play the game. S&D is a game where you drop blocks by sliding lines of colored puzzle pieces and the goal is to match three or more to break them and activate special bonuses. It would probably be fine if it didn't have in-app purchases, energy timers and best values. This might sound a bit reductionist - I'll admit I haven't played that game for very long - but putting your worst foot forward isn't a way to make me care.
The core concept of the game itself - switch and drop blocks - is okay. By combining more than three of them, you get a special block that can clear lines or rows, or explode around it. By completing levels, you build up little pictures if you get enough stars. The simple idea of the game - and potential enjoyment derived from it - makes it even more frustrating when you lose at the fourth level, where you have to break X blocks in Y seconds. You can buy more time using coins, or lose one heart, and the hearts don't replenish immediately.
Where's the actual puzzle if you can bruteforce your way through any part of the game? How can you not doubt the actual 'puzzling' value of the puzzles if the game is built around buying coins or waiting for timers to tick away? I make this very point often in mobile games and S&D won't escape it. Potentially okay concept, self-harmed execution.
