This document discusses different approaches for building mobile sites and apps with Drupal, including native apps, mobile sites, responsive design, and Drupal 8 initiatives. Native apps are extremely popular but time consuming to build and require additional skills. Mobile sites require maintaining multiple versions, while responsive design uses a single, adaptive design that scales across devices using CSS media queries. Drupal 7 supports responsive design out of the box as well as services and mobile tools modules. Drupal 8 aims to improve the mobile experience through initiatives focused on mobile, HTML5, and web services.