I do not agree. They don't necessarily need to control the mobile platform, but they do need access to the distribution channels.
Witness how Apple replaced Google Maps with their own solution, even before their solution was good enough, as if they couldn't wait to get rid of GMaps. At some point not so long ago, they also threatened to replace Google's search engine with Bing by default. In 2009 Google Voice was also rejected from iTunes because it was "duplicating existing functionality".
Google is basically playing Microsoft's own game from the nineties - controlling the platform makes them a valuable distribution channel, ensuring not only their survival, but also giving them leverage in expanding to new markets.
Google is bigger and much more dangerous today because of Android, which IMHO is vital for them going forward.
In iOS 7, Siri (the only search interface Apple cares about) will search Bing by default. Source: http://appleinsider.com/articles/13/06/10/a-wiser-siri-snubs...
You've got to admit though that, the move was highly political, from both sides, Apple didn't want to provide Google with a bunch of data so Google refused to allow Apple to have turn-by-turn directions (because they happened to be supporting a competing platform), so Apple basically said screw you Google, we'll make our own maps.
Just like their search engine? They have been flushing cash down the "online services" drain for years, with nary a profit to show, nor any progress in market share. Why should the phone market be any different? They'll keep subsidizing the "WinPhone by Nokia", and flushing cash down this new drain too.
I'm seeing parallels between their attempt to break into the search engine market, and the smartphone market.
Cash is the one thing Microsoft has. Ability to make tons more cash over the next few years (at least) is another one.
Oh, and their market share in increasing http://www.brafton.com/news/google-bing-gained-search-market... , albeit at Yahoo's expense. Who knows, 3 years from now Microsoft might outbid Google on Firefox or maybe anti-trust will not let Google buy more traffic, being essentially a monopoly and all.
Bottom line: Microsoft is in for the long, long run. So is Apple and so is Google.
This whole post reads like a warning about the sunken cost fallacy!
If Android magically evaporated tomorrow Google would be just fine -- the core of their business (ad sales) doesn't fundamentally require that they control the mobile platform, although it certainly makes things easier.
Microsoft, on the other hand, had for decades been the platform company. They've historically tried to grow by pushing out from their desktop beachhead into other territory they think they can control the platform for (i.e. servers, game consoles)
Now suddenly they've found themselves behind in the highest-growth segments of the industry. In fact, just "behind" doesn't do their situation justice: they've had to spend billions just to claw themselves into a distant third place.
I expect that those billions will keep flowing. Microsoft is desperate to win this thing.