Nice idea.
I'm normally crap at puzzle games, but even I found this one a bit too easy. Having said that, I couldn't get to play the hard levels even after completing all the others... It's a cool idea that could be expanded on a bit, with different items to collect/buy (the coins seemed somewhat pointless, unless I missed something) and more varied and challenging levels.
Think you may have a couple of little problems to iron out (I started on normal difficulty and the tutorial was still giving me instructions after I'd encountered all the different features on the very first level...) but it's a nice undemanding timewaster (dunno about Hard cos I couldn't play it, but Easy and Normal combined took me about 20 minutes) and I hope there's a sequel!