Handy module that can display a menu accordion.
First you must specify in the settings which menu that you want to appear as accordion.
There is one fundamental difference ... The main link can not be used as a link. It serves to expand or collapse the accordion. You have to create so an extra menu item and set # as link.
The main link should also be set to expand.
For the rest it is a block as another that you can place anywhere.
I find this module very convenient. For small screens they work perfectly. A nice alternative to the built-responsive menus in some themes.