An excerpt from http://www.sitepoint.com/building-great-mobile-menus-website/, by @simoncodrington
Websites need to look great and have optimal functionality, regardless of whether they are viewed on a laptop, tablet all mobile phone. Developers are adapting to a mobile-centric design philosophy with a focus on creating legible sized fonts, making images responsive, adapting content to fit etc. However, menus themselves are often neglected or overlooked. In this tutorial I will explain how to create mobile friendly menus.
Mobile menus and their importance
A Typical menu
Mobile menus have specific considerations:
Smaller device sizes
There is less physical space, meaning a way is needed to organize the menu and its links in an easy to use way. Mobile menus achieve this by either customizing the main menu or showing another menu exclusively for mobile devices (such as on phones or tablets)
These mobile menus should be free from clutter and appropriately sized, allowing users to navigate through them with ease.
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