How do you test functionality across browsers and devices?

My Google Fu is failing me today...

I want to expand the number browsers I support for my application. The amount of time it takes to test my existing functionality and on multiple browsers has become a limiting开发者_Go百科 factor for expansion.

Is there a more pragmatic what to test layout and functionality across the various mobile and traditional web browsers?

Welcome to the world of development :)

IOW, no - you need to test each release for compatibility across all the devices that you want to support.