This reminds me of a rather interesting design decision I encountered with Windows Phone this summer. I'm still undecided as to whether it is a good design or not.<p>So, over the summer I was traveling through Europe and lost my phone in Italy. I have two factor authentication on for my Microsoft account so this was somewhat of a problem seeing as every way to authenticate myself was with the phone (text, email, auth/code app).<p>Then I remembered I could go online and locate my phone through some web-app on windowsphone.com. This seemed like a terrific idea. So I went there, and, unsurprisingly but disappointingly, was unable to login because that app was not excluded from two factor authentication.<p>It was extremely frustrating to say the least.