BlackBerry is trying to be relevant again with its new Priv phone. Has it succeeded? Read on.

While some reviews for BlackBerry’s new keyboard-toting $699 Android phone find plenty to praise, other reviews pan the device and raise some red flags. Whether those red flags are simply early kinks that will be quickly ironed out, time will tell. Whatever the case, BlackBerry must deliver a stellar phone that attracts lots of new Android users if the company needs, as its CEO has said, to sell five million smartphones a year to be profitable.

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Here’s what reviews are saying about the return of the BlackBerry.  

Android Central: “Buy.” The physical keyboard is what defined the Blackberry before and it’s the defining element on the Priv. The physical keyboard is good enough that Android Central says “buy it.”   

Keyboard upsides include a design that allows swiping left-right/up-down to navigate websites and apps. The upshot is that you can use the keyboard to scroll through web pages not unlike a trackpad, the review said. And the device's virtual keyboard supplements (not mimics) the hardware keyboard by providing more options.

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Overall, the review said that BlackBerry “has crafted an exceptional little computer. It looks great, feels solid.”

But a second take, albeit positive overall, at the same tech site complains about build quality. “If I had bought this phone with my own money I would be returning it and trying again,” the second reviewer writes, citing an issue with the "squishy" back cover that “others around the web have experienced.”

TechnoBuffalo: “Buy.”  The Priv “has a beautiful screen, a great camera, a slide out keyboard that’s also a trackpad, [and] pretty solid build quality,” the review said in a YouTube summary of a written review.  The reviewer liked the curved display (which “waterfalls” on each side), providing a “useful set of icons” such as a calendar and access to the BlackBerry Hub (a vehicle for managing email, texts, and calls) when swiping from the left or right.

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On the downside, the review says the Priv gets “uncomfortably warm” at times, an issue mentioned in other reviews.

Ars Technica: “No thanks.” The review’s subhead says it all: “$700 for a bad keyboard, poor camera, iffy build quality, and old software? No thanks.” Ouch. And Ars Technica has a laundry list of reasons not to buy the phone. “Being a BlackBerry, the Priv of course has a hardware keyboard, but the keyboard isn't any good. It's so flat and tiny that it's awful to type on; we greatly preferred the packed-in software keyboard. Still, the biggest disappointment is the price: a whopping $700.”

The Verge: While more upbeat than Ars Technica, The Verge says the phone isn’t ready for prime time.  But let’s start with what The Verge says is good about the phone. “It's a fine keyboard, and it registers my keypresses without fail, even when I type quickly. It's laid out in classic BlackBerry fashion, the better to appeal to people whose thumb muscles still remember their [Blackberry] Bolds.” And the review says that BlackBerry has made the device thin despite having that built-in keyboard.

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Now the bad news. Like other reviews (even the positive ones), heat is a problem. “I've had issues with both heat and performance,” the reviewer said.  “Both are not what they ought to be on a phone at this level. In fact, the very reason this review didn't come out alongside all of the other Priv reviews is that my first unit froze itself into oblivion no fewer than four times.”

Most of the reviews imply that BlackBerry could have a successful phone but only if it quickly addresses some of the build quality issues and heat/performance.  We should know in six months or so whether it’s on the road to 5 million new users a year -- or oblivion. 

When contacted by Foxnews.com, BlackBerry addressed the back cover and overheating issues.

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"We are...aware of a handful of reports on devices whereby the back of the device is allegedly too flexible, and are continuing to investigate these reports," a BlackBerry spokesperson said in an email.

"On temperature: Part of this is our desire to fit everything into one device, including the long lasting battery, but the device is comparable to phones in that same processor range."

"On performance: We’ve asked reviewers to update their OS after receiving the device and that has solved the app performance issues. We are also working on an OS update which will be available in the next few weeks to address some of the other issues."