Source: Google.

Over the last year, Alphabet's (NASDAQ:GOOG) (NASDAQ:GOOGL) Google has seen the popularity of its mobile browser surge. In November, Google announced that Chrome's mobile user base had doubled in the last 12 months.

Most of Chrome's growth may be coming from Google's mobile operating system, Android, but Chrome is also accessible from iPhones and iPads. The continued popularity of Chrome is a positive development for the search giant, as it faces growing competition from Microsoft (NASDAQ:MSFT) in the browser market.

Nearing 1 billion users
In May, Google announced that its Chrome browser had more than 1 billion users in total but didn't break out mobile and desktop users. Chrome is the default browser for many (though not all) Android devices, and can be downloaded to an iPhone, iPad, Mac, or Windows PC. At its Chrome Dev Summit last month, Google announced that the mobile version of Chrome had grown to 800 million monthly active users, up from 400 million in the same period last year.

Chrome is now the most popular mobile browser, according to Net Applications, with about 40% market share. That's up from about 27% in January. Chrome's growth may be due to the increasing number of Android devices being shipped worldwide. More than 1.16 billion Android devices will be shipped in 2015, according to IDC, up from around 1 billion in 2014. The second-most popular mobile browser, Safari, saw its share fall modestly during that same time period, from about 43% to around 36%.

Chrome is strategically important for Google
Google doesn't profit from Chrome directly, but it's strategically important. Chrome serves as a platform for many of Google's services and encourages users to turn to Google when it comes time to search the Web. Typing in the address bar prompts a user to conduct a Google search, while a Gmail account can be used to sync browsing history, bookmarks, and settings across a variety of devices.

Google also uses the popularity of Chrome to influence the development of the Web. Recently, it introduced an API for Chrome that allows websites to interact with Bluetooth devices -- a feature that has typically required the use of an actual app installed on a device (a native app). Google has introduced new technologies that allow its search engine to look inside native apps, but the increasing use of native apps in general (as an alternative to traditional Web pages) has long been seen as a threat to Google's core search business.

Microsoft targets Chrome
Perhaps the best testament to Chrome's importance are the steps Microsoft has taken to discourage Windows 10 users from installing it. Microsoft's latest operating system, Windows 10, ships with a new browser from the Redmond tech giant, Microsoft Edge. Edge is tied directly to Microsoft's own competing online services, including, most notably, its search engine, Bing, and its digital personal assistant, Cortana. Windows 10 users who attempt to install Chrome are shown a prominent warning message that encourages them to rethink their decision.

Bing achieved profitability for the first time last quarter, largely due to strong Windows 10 adoption. Windows 10 users that opt for Edge over Chrome may wind up conducting more searches through Bing. Yet when it comes to browsers, Microsoft has almost no mobile presence. Edge and Internet Explorer are mostly restricted to Microsoft's own operating systems, and Windows Phone's share of the mobile market hovers in the low single digits.

That's given Google an opportunity to dominate the market for mobile browsers. With 800 million active users and rapid growth, it's clearly doing so.

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