One thing I’ve noticed while working with iOS is that magic strings seem to be quite common.
They’re in Core Data:

[NSEntityDescription insertNewObjectForEntityForName:@"Foo" inManagedObjectContext:context];

They’re in Storyboards and View Controllers:

[self.storyboard instantiateViewControllerWithIdentifier:@"SomeViewControllerIdentifier"];

They’re in Segues:

[self performSegueWithIdentifier:@"SomeSegueIdentifier" sender:self];

They’re in sorting:

NSSortDescriptor* sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name"
                                           ascending:YES];

They’re in the instantiation of table cells:

static NSString* CellIdentifier = @"Cell";
UITableViewCell* cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

Coming from the C# world of lambdas, generics, first-class enums, and strong typing, I find all of this incredibly bizzare. But hey, who needs refactorability and type safety when you can use strings!