A modern twist to testing in application development is the emergence of mobile devices as platforms for web applications. The challenge, of course, with mobile applications is in testing the application across a wide range of device form factors and browsers. One tool that can be very helpful in this endeavor is using a utility such as BrowserSync, which uses web sockets to synchronize interactions in your application across multiple browsers or devices.
This may seem abstract at first, but the idea is that it allows you to run your application from one central location, and have multiple devices follow your user interactions simultaneously. This can help reveal browser-vendor specific compatibility problems in your web application. This sort of multidevice testing itself isn't automatic; however, the setup with BrowserSync...