iPhone: Save boolean into Core Data

Core Data “does not have” a Boolean type (it does, but it is an NSNumber).

So to set the equivalent of useGPS = YES.

[entity setUseGPS:[NSNumber numberWithBool:YES]];

And the other way around:

BOOL isGPSOn = [[entity useGPS] boolValue];

Update:
As pointed out by SKG, With literals in Objetive-C you can now do it in a simpler way:

[entity setUseGPS:@YES];

BOOL isGPSOn = entity.useGPS.boolValue;