First of all get Cheat engine from the internet, once you install it, open cheat engine and select the current processes (make sure Fruit ninja is running!!) and select fruit ninja, then play fruit ninja at the same time. When in the middle of gameplay when you get a score number of 1 and above, go back to cheat engine and type in the nuber of score and hit next, now go back to fruit ninja and get another score and go back to cheat engine and type in the number of the score again, repeat the steps above until the number of your current score only has one or two copies, THEN change the number to 999999999999999999999999 or any large number and hit OK, and ther you have it! You have h a c k e d the high score of fruit ninja!