Yeah, we know our front page is lousy right now; we've got a redesign and a much clearer explanation in the works.
You need our service to make sure your web apps work in all the popular browsers.
We've got a bunch of web browsers in the cloud which you can remote-control via and API, to make sure the features of your site work cross-browser. We use a popular open source browser automation tool called Selenium, which my cofounder Jason Huggins created.
I'm curious whether the above description makes sense, or still leaves you scratching your head!