The figures are in: In the third quarter of 2012, no less than 75% of smartphones shipped ran Google’s Android operating system. This equates to 136 million Android handsets, almost doubling the 71 million Android smartphones from the same quarter last year. If we look at the entirety of 2012 to date, 68.2% of smartphones sold are powered by Android, up from 49.2% last year.

In 2008, manufacturers shipped 0.7 million Android devices; by the time 2012 draws to a close, there will be roughly 550 million Android devices in circulation, capturing 70% of the smartphone market. While IDC is only measuring shipments, Android’s 136 million shipments in Q3 2012 correlates rather nicely with Google’s figure of 1.3 million device activations per day — so we can be fairly sure that these figures aren’t skewed by Android devices sitting on the shelves of retailers. Rounding out the rest of the smartphone market, Apple shipped 26.9 million iOS devices in Q3 2012 (up from 17.1 million in Q3 2011), and RIM, Symbian, and Windows Phone all wallowed around the few-million mark.

In short, Android is exploding in a monumental fashion — and unless Windows Phone surpasses all expectations (and then some), or Apple produces an iPhone 6 with holographic display, it doesn’t seem like Android is done yet. If the trend continues, and the smartphone market continues to expand (which it will for the foreseeable future), then we could be looking at an Android market share of 90% by the end of 2013. 90%, just like Microsoft’s share of desktop PC market. 90%, a complete monopoly of the smartphone market.

What will happen when Google has a monopoly of the smartphone market? Well, Android and Windows are obviously very different beasts, but we can still try to draw some wisdom from Microsoft’s 20-year reign.

For a start, Google will have almost complete control of the direction of the smartphone market. If Google decides that HTML5 web apps are the way forward, making them a first-class citizen in future versions of Android, then other mobile OSes will have no other option than to follow suit. Conversely, Google could decide to cease development of the stock Android browser — much like Microsoft did with IE4 — and push alternative technologies like Native Client or Dart, forcing other mobile OSes to embrace Google’s tech.

And what about the other platforms? It seems like Apple is destined to occupy a tiny corner of the market — no doubt making fat profits, but losing control of the market and all-important mind share in the process. As we’ve discussed elsewhere, Microsoft really needs Windows Phone to succeed — but it will take a miracle to turn OEMs away from a proven OS like Android (and it’s free, unlike Windows Phone).

You may point to the fact that Android is open source, thus making such a monopoly rather toothless. This might be theoretically true, but in practice Google still holds all the keys. Yes, if Google goes off the rails, another company or group can take up the slack — but when you’re dealing with hundreds of millions of devices, and relationships with thousands of OEMs and mobile carriers, it isn’t like Google can just be pushed aside. Can you really see people giving up Google Android for Open Android, and losing access to hundreds of thousands of apps, their Google Drive, Gmail, and other assorted features?

Over the next few years, Google will develop unprecedented control of the fastest growing tech market in the world. Will Google use this power to gently steer and cajole the web and mobile computing markets towards green pastures, or will it cave like Microsoft and squeeze as much money as it can from Android?

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