Registration
Sokoban is shareware. This means that you can download and try Sokoban for a period of 30 days. During the trial period, the game is fully functional. After the 30 day period you are required to register Sokoban at ShareIt

Discount
You can earn a discount on the registration fee by solving levels. The more levels you solve the lower the price will be.

Solved levels    Discount
35%
1010%
2015%
4020%
10030%