This game is so well polished I'm impressed! I really like the smooth animations for the shop and card, and I think it's a very creative idea to use cards to change the physics of the ball!
I think you should make the wheel like, more similar to an actual roulette wheel. As it stands right now, the same thing happens every time at the end. The ball is in one colour, the wheel moves up, the slides down , and it either falls into the adjacent colour, or it skips over one and lands in the same colour. It always does one of two things at the end and it makes it a little samey and makes the entire opening first 10 seconds feel pointless.
However, that is just a small gripe, and overall I really enjoyed this game! I would love if you added more cards and betting options, and really made you able to completely change the roulette wheel in your favour!