HTML5 APIs help developers write mobile web applications that provide native application features. While this may suffice to a large extent for a certain class of applications, often it is found that there is a requirement to integrate one or more device (native) capabilities in these mobile web applications.
The project is available on GitHub and has several sample projects that you could check out. Documentation is well structured with a Getting Started guide to get you off the blocks quickly. The bridgeit.js code is free and licensed under the Apache 2 Open Source license. The BridgeIt Utility Apps are also free and licensed under the BridgeIt Utility App License.
The BridgeIt library looks promising and integrating it in your existing mobile web applications looks really simple. We don't expect mobile devs who are already using other approaches to switch to BridgeIt immediately, but it provides a very compelling option to integrate a device feature or two in your mobile web applications.