I prefer Testacular for exactly this reason. It allows you to capture any number of browsers. I've attached my physical iPad to it, and IE 8 out of a VM. JsTes

I prefer Testacular for exactly this reason. It allows you to capture any number of browsers. I've attached my physical iPad to it, and IE 8 out of a VM. JsTestDriver and Test'em 'Scripts do too. (I haven't tried Test'em yet, but that's what I hear.) Granted, these aren't tools for functional testing like Selenium and (apparently) CasperJS, but functional tests are something you want to minimize as much as possible. They're slow-running and brittle.