This example shows how to use fast enumeration in order to traverse through an NSArray. With this way you can also track current object's index while traversing.
Suppose you have an array,
NSArray *weekDays = @[@"Monday", @"Tuesday", @"Wednesday", @"Thursday", @"Friday", @"Saturday", @"Sunday"];
Now you can traverse through the array like below,
[weekDays enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
//... Do your usual stuff here
obj // This is the current object
idx // This is the index of the current object
stop // Set this to true if you want to stop
}];