In this game you gradually make your way up to all levels.
Your calculation speed will increase, and you are going to
be able to solve mathproblems much faster than you used to.
Try to get all achievements and declare yourself a true
Update: I realised there was a security issue when saving the game. So I fixed that and now everyone can save their game properly.
Update: Thanks to my little brother a huge bug was discovered. Apparently the level select system which shows locked levels didn't get the right data for unlocking the levels. This is fixed now and I apologise for this mistake. Also when you gain five stars (50 sums correctly answered) the fifth star wasn't shown in the feedback page. This is also fixed now.