Too difficult towards the end.
This is a very well made, and original to an extent game. The graphics were crisp and there was a good learning curve. Well done.
My only complaint is after level 6 or so, the game started to get really difficult. I couldn't even finish level 8, no matter what I tried (Combos to increase score took too long, no combos to increase speed didn't work, combination of both worked even less.)
I know I shouldn't downvote the game because of its difficulty, but for a game with such a relaxed learning curve to suddenly go so hard, I cant finish even after 4 retries is a bit... Unfair, to say the least.
That's my only negative comment though, the rest of the game was brilliant. Maybe you could add different characters throughout the game? I dont think I've ever been more irritated with 2 customers and a phone ;D.