Sounds like it uses some of the concepts in Epic Mickey 2 and The Unfinished Swan. You should think about how to differentiate your game from those two.
How is it similar to those games?
first off, those games are completely different. meaning that they don't use most of the gameplay that I mentioned like for example being turned into another colour to have another ability and its all about ink. So when I said that some places will be in black and white, it doesn't mean that the whole section is going to be black and white and that you can't access that area until you color the picture frame hidden somewhere in the level. my game is 2d as well and that in inkman, you control a fluid character. My game doesn't use erasers or pencils to draw nor does the colour change the white pictures in the level. you can absorb colors as a source of energy but only the color that inkman is in.
so maybe its similar to epic mickey 2 but not so much. Inkman transforms into a color which gives an essence to him. If he's orange he has the ability to bounce and if he's green, he can melt metallic objects. But these also affect him as the more he uses his ink, the more he becomes white and when he gets hit in his white form once, he dies.
if its still too similar, I don't think its such a problem to me as I still feel that its different from those two.
My only wish is that I can understand how my game will look like in terms of art because I love pixel art, and anything that looks gorgeous like rayman origins or de blob.
Can I ask weather this game can work on smartphones or am I better off making it on ouya? Because To me I personally feel that controlling the character on smartphones will be difficult since these smartphones have this fake d-pad for movement blocking the level part.