This is the start to a cool game! I think the one thing it's missing is a change up. The color / word challenge is a challenge because we try to read things before we consider the color of things. So, to make it more interesting you could use a keyword like "color" or "word" to change what you need to catch. All that to say, the word / color thing isn't confusing, it's a cool concept for a game.
Also, not sure if this is a bug, but I lose a life no matter what I do. If I catch the right color, it's fine, but if I let the wrong color touch the ground, I lose a life anyway.