Complicating matters is the decline in shipments of the Nokia feature phones Microsoft also acquired.
To significantly boost Windows Phone sales, Microsoft needs to sign big partners that can sell millions of devices per quarter. Getting them onboard is one of many things Windows 10 is expected to help with, and there is some positive momentum.
The OS will feature an updated user interface and a host of improved applications, such as the new Spartan browser. It also provides more integration between PCs and smartphones, including the ability to see notifications across different devices.
Chinese vendor Xiaomi recently announced that some users of its Android-based smartphones will be able to test Windows Phone 10 by installing it on their phones. Getting Xiaomi onboard would be a big win for Microsoft. The company has become one of the world's biggest smartphone manufacturers, even though it doesn't sell its products in Europe or the U.S.
Microsoft has struggled to get the biggest smartphone vendors to back the OS. For example, Samsung has only launched two Windows Phone devices in the last two years, and it didn't give them anywhere near as much marketing support it gives its Android smartphones. Samsung declined to comment on its plans for Windows 10.
One smaller vendor backing Windows Phone is Florida-based Blu Products, and while its CEO Samuel Ohev-Zion is very critical of the Nokia acquisition, he has high hopes for Windows 10 and its expected ability to attract more users and developers.
The deal overvalued Nokia's assets, he said, because it has become much easier to develop smartphones. And not getting the valuable Nokia brand as part of the acquisition was a big mistake, he added. Microsoft has been using its own brand on Lumia smartphones since October.
Windows 10, on the other hand, is going to be groundbreaking, Ohev-Zion predicts. The biggest turnoff with the current version of the OS is that users aren't familiar with the interface and don't understand how it works. But that will change with Windows 10, because the experience on PCs and smartphones becomes more similar, he said.
Microsoft is also doing the right things from a software development perspective, according Ohev-Zion. With Windows 10, developers will be able to build so-called universal apps for PCs, tablets, the Xbox game console and smartphones. That will help open up the platform to a much larger developer audience, he said.
The launch of Windows 10 is expected to be followed by the arrival of Microsoft's first high-end smartphones. The company will make sure it has products in this market segment, but making a dent is very difficult, thanks to Apple's and Samsung's dominance, according to Christophe Francois, vice president of strategy and business development at telecom operator Orange.
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