Mobile-friendly design
I work part-time as a freelance Drupal module developer based in the UK
On Drupal.org for 10 years as AdamPS
More and more people are using smartphones, tablets and other other devices to use the Internet, so it is important to create a website that is easy-to-read in a variety of different screen sizes (using a mouse or a touchscreen). By easy-to-read we don't mean a very tiny version of your page, we mean a page that re-formats itself so that the important information is right there front and centre all the time. The technical term for this is 'responsive design' and we do it.