Android: Doesn't have the dominance that Windows has had for two decades, thus limiting the power of Google. Also, there is much less lockin for phones.
Google builds an AOSP environment, as soon as everyone uses it, they move all the libraries into the proprietary Google Services Framework, and then they appended their contracts so that every manufacturer that produces "Android with Google Play" devices can’t sell pure AOSP devices anymore.
The vast, VAST majority of APIs that developers use and depend on are in AOSP either as framework APIs or in the support libraries (which are open source in AOSP as well).
Second the contracts were always there. Hell, the contracts (Open Handset Alliance) came before AOSP.
"Microsoft has no marketshare", "Microsoft just doesn't get it", "Microsoft lost the war", "Microsoft is dead".
http://markets.ft.com/research/Markets/Tearsheets/Financials...
Microsoft is still an incredibly powerful company.
Meanwhile I'm using my cell phone dozens times a day and a tablet at least 3-4 times a day.
Man this must be terrifying for Microsoft. To have a dominant position on a form factor that is quickly becoming irrelevant.