CrossBrowserTesting is a company offering browser and mobile device testing; its blog covers testing tools, Android fragmentation and screenshot comparison.
HN commenters recommend the service for testing sites across browsers and operating systems, calling it affordable and easy to use.
Yes - I read the article.
Phones and tablets come in hundreds of different screen sizes. Ever see this map?
https://crossbrowsertesting.com/blog/mobile-devices/android-fragmentation-web-app-quality/
There isn't a "typical" shape / size for a phone / tablet.
You can say an iPhone screen size when duplicated into 2 side by side does not equal an iPad screen size, landscape or portrait and I'd completely agree with you. But to say a new class of device won't have it's screen sizes and needs to conform to screen sizes of the past... that just doesn't make sense. No one conforms to screen sizes; past, present, or future.
If you're looking for a service that's live, I've been using http://crossbrowsertesting.com/ happily for the last two or three years.
Also, if you're testing emails in different clients (worse than IE6 compatibility testing IMHO), I highly recommend http://litmus.com/
This can be accomplished with:
http://crossbrowsertesting.com/
The service allows you to pick your platform and installed browsers and then do whatever you wish on a virtualized instance. You can get 5 minutes free, otherwise there are paid options.
I've had great experience with http://crossbrowsertesting.com/, it costs $29.95 per month. I can't recommend it enough. You can't start a VM from a desktop program but all it takes is a few clicks in the browser, and everything works like a charm.
I will take this opportunity to keep plugging for http://crossbrowsertesting.com/
I'm not affiliated with them in any way, they've just made my one of my jobs much easier for not much money, and they hang out on HN sometimes besides.
http://crossbrowsertesting.com/ is an alternative that has proven very good and cost effective for me.
This does appear to be cheaper though. The local testing thing may be cool. Not sure how that will work.