One of the great challenges in delivering content to the mobile web is that mobile devices can easily be disconnected from the Internet. As users move around, they go in and out of range of WIFI and cellular networks, and the state of their network connection can change frequently. Native applications on mobile devices solve this problem by being installed on the device. Many native applications also cache content for offline use and are designed to handle the transient nature of mobile network connections. Web browsers, including mobile web browsers, typically cache web page content to help pages load faster. While this can help mobile web applications quite a bit, the cache managed by the web browser is unreliable, can be cleared by user settings, and might not keep critical content for your application. The cache also doesn't provide a mechanism to store generated data and stores only assets required to load a web page.

In this section, we will introduce three technologies...