I've actually purchased this game twice on two different devices. I'm sure I could have figured out to transfer the purchase to my new device, but honestly, this game is worth paying for it twice. We homeschool and my 8-year old had no idea he was learning actual algebra until after he finished the entire game and I had him start completely over and showed him HOW it is the same as algebra. I don't think I would change a thing, except that in all reality, your child could finish this game and if you were to introduce them to real algebra, they would have no idea what to do at first. You really should go through it with them and compare the two together and make it a learning experience. Don't expect an app to teach your kid anything, but it is certainly a cool game with rules that are basically the same as algebra. I'd recommend it to anyone with kids above 5 years old even..