After the launch of the Apple iPhone in 2007, and after Android phones started getting really good, iOS and Android devices began their sustained assault on market share, and today they dominate totally.
From the perspective of who is making the majority of physical smartphone handsets, the clear leader is South Korea's Samsung, which sells more than one quarter of the world's smartphone handsets, followed by Apple, which sells about 18 percent. No other company gets anywhere near a two-digit market share globally.
From the perspective of platforms - who makes the operating systems and controls both the functionality and the app ecosystem that powers the world's smartphones - it's clear that Google's Android is by far the world's leader, followed distantly by Apple's iOS.
From a business perspective - who's making money on mobile phones in one way or the other - the clear winners are Apple, Google (via advertising, mostly) and Samsung.
So today, we can say that the smartphone market is solidly controlled by two companies that are less than nine miles apart from each other in Silicon Valley in the US (Apple and Google), plus Samsung in South Korea.
These three companies in two countries ship the handsets, make the operating systems and collect most of the profits.
But what will the mobile market look like five years from now?
Meet the new operating systems
All is not well in the universe of mobile platforms, or operating systems.
Apple's iOS platform used to be much better loved by Apple fans. It had by far the most and best apps, and it was perceived by most to be innovative and leading edge.
But the Android platform is either catching up to, or has already surpassed, iOS in both innovation, as well as the quantity and quality of available apps. When you combine software improvements on Android with a vastly greater variety of available handsets, many former iPhone users are defecting to the other side, or thinking about it.
While users are growing ever fonder of the Android platform and its apps, hardware makers that create Android-powered phones are growing less fond. The issue is direct competition from Google itself.
Google has twice launched phone initiatives where it decided to sell Google-branded phones. The first initiative was in early 2010 when Google launched the Nexus One, followed by the Nexus S. They were manufactured by HTC, but the fact that Google was involved in their design and sold them directly gave the phones a huge advantage over any phone HTC might sell - or any phone HTC's competitors might sell.
Google later came out with the Galaxy Nexus (made by Samsung) and later still the Nexus 4.
Google also bought Motorola last year, both for the patents and also presumably to assert some control over the direction of Android mobile devices.
The first serious assertion of that control may be the development of a device called the Google X phone, which is being developed at Motorola and which is expected to be unveiled at Google's May developer's conference, Google I/O.
Nobody knows what the Google X phone (and tablet) will be like, but hints, rumors and speculation agree that it will be very different from existing Android phones.
All this strong competition from Google makes handset makers wonder whether Google is friend or foe, and whether they might be better off with another software platform.
These disaffected Google partners may be looking more closely at Microsoft's Windows Phone 8, now that Nokia reported some impressive numbers (both of which included the numeral 4, oddly enough): The company sold 4.4 million Lumia Windows Phone devices and reported a year-over-year quarterly U.S. market revenue increase of 444%.
Although the market punished Nokia's earnings, a careful analyst might notice that Nokia's Lumia line failed horribly in the so-called "emerging markets" of China and elsewhere, but succeeded in the US and Europe. The company is making more money on far fewer handsets than before. In other words, Windows Phone 8 may be helping Nokia's economic situation become less like Google's (high volume, low margin) and more like Apple's (high margin, low volume).
Beyond iOS, Android and Windows Phone, there are other emerging platforms under consideration by some current Android handset makers.
In fact, Google's biggest and most profitable Android partner, Samsung, is supporting a new platform called Tizen. (Intel is also a backer.) If Samsung switched from Android to Tizen, the phone platform scene would be transformed overnight. The first Tizen devices are expected within three months.
The people at Ubuntu Linux, the most popular client version of that operating system, are building a version for smartphones.
HP's WebOS, acquired from Palm, is still a potential factor, especially since HP plans to release an open-source version called Open WebOS.
Note that all of these platforms -- Tizen, Firefox OS, Ubuntu Linux and Open WebOS -- are Linux-based and all or most will be relatively open compared with Android.
Meet the new handset makers
While upstart platforms threaten to take advantage of weaknesses in the iOS and Android worlds, a similar thing is happening in handsets.
Right now, Samsung and Apple dominate. But in China and in other markets, Chinese companies are growing faster than the global leaders.
Sometime this year, we'll reach the point where half the mobile phones sold in the world will be smartphones, rather than feature phones. The reason for that shift is partly caused by a drastic reduction in pricing for smartphones, thanks to low-cost Chinese brands. And also high-end brands.
In China itself, for example, Samsung is the No. 1 handset maker. But No. 2 is Lenovo, a Chinese company, and its handset business is profitable, too. According to one article, there are more than 100 Chinese companies now making smartphone handsets, and they all want to be Samsung.
Rumours have been circulating that Lenovo is in talks to buy RIM -- a development that, combined with continued aggressive growth, could thrust Lenovo into Samsung territory as a global maker of phones.
So if Samsung is No. 1 and Lenovo is No. 2, Apple must be No. 3, right? Wrong!
These companies, especially Huawei and ZTE, are bringing the smartphone revolution to emerging markets, for the most part. And now they want entry into the U.S. and European markets. Huawei and ZTE each had a large presence at the International CES trade show, which served as a kind of coming out party for those companies in the U.S.
Samsung and Apple fans may scoff at the idea that some obscure Chinese brand like Huawei or ZTE could take market share away from the leaders. But if either or both of these companies can make phones that are 95% as good as Samsung's best phone, and cost half the price, people are going to buy them in large numbers.
Apple, Google and Samsung control the global market for smartphones. But over the next year or two, all that could change as new software platforms and new handset makers take advantage of the leaders' stumbles to gobble up market share, market power and influence over the direction of mobile devices.
Mike Elgan writes about technology and tech culture. You can contact Mike and learn more about him on Google+. You can also see more articles by Mike Elgan on Computerworld.com.