I like it too - enough to make several changes for my own use. It will be several days before I have time to work on it. Maybe you will beat me to it?
This is not meant to be negative, but here are the things I would change:
1. First and foremost, the graphics do not display properly on a device with scale = 1.5 (240) -- see attached screen shot.
2. To echo the previous comment, I would make changes to the display of information and the buttons. The large white boxes dominate the screen, they should be secondary to the slot machine.
3. On all slot machines, the bet is subtracted immediately when the machine is activated. On yours, it is subtracted after the spin and payout is calculated - and then only if you lose. So, for example, if you start with 50 coins and a cherry comes up you show 52 coins (2 for the cherry win). It should be (50-1) + 2 = 51 coins.
4. The payoffs are WAY too high. No fun at all to play a slot machine you can't lose on. I would limit the expected payout to 100%.
Thanks for sharing your slot machine!