The iPhone has become a gold mine for those who create games for the device . Steve Demeter developed the popular puzzle game `` Trism '' in his spare time . He also created an app called " [ Tris ] ( http://tris.io/ ) ` It 's a very simple-to-learn , hard-to-master puzzle game . The App Store has helped open the game-development field to entrepreneurs .
The iPhone has become a gold mine for those who create games for the device . Steve Demeter developed the popular puzzle game `` Trism '' in his spare time . He also created an app called " [ Tris ] ( http://tris.io/ ) The App Store has helped open the game-development field to entrepreneurs .