Offline-capable applications with HTML5

Without a Net


An offline cache in your browser and a bit of HTML5 acrobatics combine for interactive web applications that keep working even when the Internet connection breaks down.

Web browsers were originally simply viewers for static HTML documents. Since HTML2, browsers have had the capability to capture simple user input with forms and send it to a database on the Internet. For this to work, of course, the system must be connected to the Internet. At every disturbance of the network connection, exasperated users lose their work.

HTML5 includes some powerful features that let web applications operate offline. In this article, I introduce these offline technologies in detail. I’ll also show you how to build an example application that implements an offline-capable tool for saving geo-coordinates (geolocations). This app runs on any devices that supports HTML’s offline features, including Firefox (currently v14) , Opera (v12), Chrome (v21), Safari, and Internet Explorer (v9).