Hey there, gave your game a try. Got some feedback for you:
Overall, a pretty interesting game, the color matching twist is a fun mechanic, but it also notches up the difficulty of the classic 3-match gameplay up a couple of notches.
Some tips that will help in terms of interface - although many people are familiar with the standard color wheel having the conversions visible in the game itself will make things much easier. Additionally having the colors animate/fade (Blue + Red <fade into > Purple etc) will make the gameplay much clearer!
In terms of user interface, it would be very helpful to pop up the instructions the first time a new user plays the game (Most people go right to the Play button because they want to get a feel for the game instead of tapping instructions). Also when somebody exits a game, have it save the game instead of dumping them out to the high-score (they might not be done with the game yet!). In terms of language, try to stay away from more negative statements ("failed to achieve a new high score") and go for positive ("Close!" "Try again!" "Almost!" "Not bad") to encourage users to keep playing.
Lastly, I personally think that the color scheme could be improved by making the tiles a little softer and having some sort of non-black background.
Overall, the idea is pretty sound - I know I pointed out mostly things to work on but since you wanted feedback, I hope this helps.
