I am not a big fan of accordion in mobile development, because I believe that this behaviour is a web style user experience. However, I don't have any resource to find an alternative solution for this type of control. Our navigation has a maximum number of 3 levels. In iOS, this can be solved using UINavigationController, but it comes with a price, because when the user wants to go back to the main menu, user has to trigger 2 actions, which I think is not a good interaction with the app.
Any ideas are welcome. Thanks in advance! Cheers