Browsershots makes screenshots of your web design in different operating systems and browsers. It is a free open-source online web application providing a convenient way to test your website's browser compatibility in one place. When you submit your web address, it will be added to the job queue. A number of distributed computers will open your website in their browser. Then they will make screenshots and upload them to its central dedicated server for your review.
This looks great, I'll definitely be giving it a try.
Not automated (and definitely not as powerful as this!), but I wrote a little free iOS util to help with testing websites in different iOS browsers: https://itunes.apple.com/us/app/...
Obviously in iOS, most people still use Safari because they can't choose a new default browser, but there are still a surprising number of alternative browsers.
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