Fun Little Game, well designed.
I'm having a little bit trouble "trigger" the Jump. I think you could improve the "Jump" Action. It feels very often that you press Left and Right but he only switching direction and not register the Jump Action.
The Wall Climbing feels super Cool, Nice Levels and very Casual to collect all "Star"s and "Diamonds".
Deserves more Level's
Since i don't like Pixel Art, i suggest a better Visual Style for this Game. But this is very personal i think.
Good work, keep it up