Sony previously sold the Xperia Z3 smartphone and other models through U.S. carriers, he noted.
"Sony has always had good designs and top quality cameras and video capabilities in smartphones, but so far hasn't been able to get that into the heads of retailers, carriers and consumers," Moorhead said. "Recent Sony phones have delivered really good experiences, but their marketing and distribution has been a bit soft for the U.S. market, which is dominated by Apple and Samsung and is carrier-led."
Carolina Milanesi, chief of research for Kantar WorldPanel, said the unlocked price of $600 for the larger Z5 will probably be too high to produce big results for Sony. "With a price tag of $600, I struggle to see how they will be able to sell in volume," she said. "The unlocked market is a very difficult one. The Xperia brand is still a brand that your average consumer is not very familiar with."
IDC analyst Anthony Scarsella went further: "An overwhelming majority of consumers in the U.S. are still unaware that Sony actually makes smartphones." He said that's because Sony doesn't have dedicated support from carriers and has lacked big marketing campaigns.
But Scarsella is still a big fan of the latest Xperia smartphones and currently owns and uses the 5.5-in. Xperia Z5 Premium model. He tried out both the Z5 and Z5 Compact at the Sony booth at CES 2016 recently, and has owned the earlier Sony Xperia Z, Z2 and Z3 models, going back to 2013. (Sony has not officially put the Z5 Premium model on sale in the U.S., although it is available without a warranty.)
"The build quality of the [latest] devices is top notch and all three Z5 models feel very high-end and solid in the hand," he said. All three models come with an IP68 rating for water and dust resistance, which is not found on many competing products, he added.
The camera on his Z5 Premium is "very high end and capable of competing with the iPhone 6S and Samsung Galaxy Note 5." Many of Sony's competitors even use the camera sensors made by Sony, he noted.
Its new efforts could be a sign that Sony's worst smartphone troubles could be behind it, analysts said. In the last year, Sony's Xperia Z4v was canceled on Verizon due to a launch delay, and T-Mobile pulled the Xperia Z3, Scarsella noted. Sony even stopped direct sales from its website a few months back and there have been rumors that Sony would sell off its entire mobile division, Scarsella said.
However, more recently, Sony opened a factory in Thailand, and Sony CEO Kazuo Hirai has committed to building "products that matter" there, Scarsella said. "It's hard to tell if this 'products that matter' includes mobile," he said. "We view 2016 as a pivotal year for many large smartphone players, and Sony [has been] right at the top of that list."
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