Seeking Advice on Enhancing Security Measures for My React Native Money Game

Question

I have developed a money game using React Native, and I'm facing a security concern. In my game, I have two variables: 'score' and 'increment'. The score is initially set to 10, and every three seconds, the score is incremented by the value of the 'increment' variable. For example, if the increment is 3, the score will be 13 after three seconds and 16 after another three seconds. However, a friend of mine with a rooted device was able to access the AsyncStorage data of my game and change the values, effectively hacking my game. I'm looking for advice on how to protect my game against such unauthorized modifications. I would greatly appreciate any suggestions or best practices to enhance the security of my game and prevent unauthorized access to the AsyncStorage data. Thank you in advance for your assistance!"