AllWebMenus Pro: http://www.likno.com/allwebmenusinfo.html
AllWebMenus Pro WordPress menu plugin: http://www.likno.com/addins/wordpress-menu.html
In this video presentation you can see step by step how to create a responsive menu for your WordPress website using AllWebMenus Pro and the AllWebMenus Pro WP menu plugin.
The menu created has 2 versions, one which is a horizontal drop down menu and one that is a sliding menu. The menu version 2 is going to be displayed in tablets (portrait view) and smartphones (portrait/landscape view).