In my app\'s code I am still presenting viewcontrollers modally with presentModalViewController. This is deprecated in iOS 6. Does that mean this method has no effect on devices
Deprecated means that you shouldn't use this method anymore. It still works, but it might be completely removed in one of the next updates.
For displaying view controllers modally, you can use the new -presentViewController:animated:completion:
method introduced in iOS 5.0.
For dismissing the new method is -dismissViewControllerAnimated:completion:
.
https://developer.apple.com/documentation/uikit/uiviewcontroller
If you have
[self presentModalViewController:aController animated:YES];
change it to
[self presentViewController:aController animated:YES completion:nil];