We’re going to make a simple offline-first to-do application with HTML5 technology. Here is what the app will do:
- store data offline and load without an Internet connection;
- automatically download the latest stories when there is a good connection;
- run on the first- and second-most recent versions of all major desktop and mobile browsers;
- list the latest news headlines as well as allow users to click into an article;
- have a unique URL for each of the articles, and the list of articles page.
The last point is highlighted because it's the key distinguishing feature that makes making a website work offline different, and substantially harder, (with AppCache) than "single page apps" like the one described in the previous section.
Content-based websites (which includes websites other than news sites, such as Wikipedia, where the focus is on reading rather than doing make up a huge proportion of the world wide web) but are a use case that stretches AppCache to its limits.
This makes building a simple offline news website a good example to explore AppCache and its replacement, Service Worker, in depth. Also it will be possible to takes these tips and tricks and apply them immediately to most websites.