Microsoft's claims that Windows Phone 7.5 would beat iOS in web browsing speed have already been rendered obsolete after a follow-up test run. A comparison from YouTube user 359gsm posted at My Nokia Blog of a Nokia Lumia 800 pitted against both an iPhone 4 using iOS 4.3 and an iPhone 4S on iOS 5. While Microsoft's showcase HTML5 Speed Reading test beat the iPhone 4, even the older, 1GHz Apple phone and OS beat the 1.4GHz Windows Phone soundly in every other test, including Browsermark, the JavaScript-focused Sunspider test, and the generic HTML5 Test.
