I have some code in my classes to read from NSUserDefaults

NSUserDefaults *defs = [NSUserDefaults standardUserDefaults];
score = [defs integerForKey:@"score"];

this causes a crash.

Im guessing it is because the score value is nil or doesnt exist.

How can I check if it is nil?

EDIT.

The following code causes a crash when storing to NSUserDefaults.

NSUserDefaults *defs = [NSUserDefaults standardUserDefaults];
    [defs setInteger:0 forKey:@"score"];
    [defs setInteger:3 forKey:@"lives"];
    [defs release];

Im not sure what the issue is

On some crashes there isnt even a crash report in the console.

Thanks