i had declared a timer
[self schedule: @selector(step

];
now i want to remove this when game ends
so i am doing this
[self unschedule: @selector(step

];
it work only when 1st time game ends and rest of time i can see the value i am passing in step()
code is somewhat like this
game start()
{[self schedule: @selector(step

];
}
then
step()
{
if(gameEnd)
{
[self over];
}
}
over()
{
[self unschedule: @selector(step

];
sceneChange
}