Starting on April 8, Nokia and AT&T will begin selling the first 4G LTE Windows Phone ever released in the U.S., the Lumia 900, starting at an extremely competitive price of $99 with a contract, and $449 without a contract. Critics have begun releasing their reviews of the new Nokia smartphone, but does it stack up to the iPhone?

A jumbo-sized, suped-up version of last year's Lumia 800, the new Lumia 900 features a 4.3-inch Clear Black AMOLED display with a 800 x 480 resolution, which is all protected by a rubbery unibody polycarbonate shell that's rounded on the longer sides but squared off on the top and bottom. The Lumia 900 is also slightly thicker than the Google's Galaxy Nexus smartphone (65.5 mm compared to 67.9 mm), even though the Nexus phone has a 4.65-inch screen and measures less than a centimeter longer.

The Lumia 900 also includes 16 GB of storage (but only 14.5 GB is available), and while there's no memory card slot, Nokia and Microsoft offer users 25 GB of clou storage on SkyDrive, Microsoft's cloud platform. The Lumia 900 also comes equipped with Bluetooth 2.1 (no 4.0, unfortunately), a Wi-Fi hotspot feature, a gyroscope, 3-axis accelerometer, microSIM slot, 2 microphones and two cameras, including a 1-megapixel front-camera with f/2.4 aperture and a 8-megapixel rear camera with f/2.2 aperture, dual LED flash, Carl Zeiss optics and a dedicated shutter button.

Many critics around the country already have the phone in their hands, and their reviews range from jubilance to vast disappointment. Here's a round-up of what they have to say:

Walt Mossberg, AllThingsD:

I've been testing the Lumia 900 and found that it provides the best home yet for the attractive Windows Phone software, but still doesn't measure up to rival smartphones. ... Unless you are a big Windows Phone fan, or don't want to spend more than $100 upfront, I can't recommend the Lumia 900 over the iPhone 4S, or a first-rate Android phone like Samsung's Galaxy S II series. I was underwhelmed by the battery life, the browser, and the quality of its photos. Plus, the Windows Phone platform has only a fraction of the third-party apps available for its rivals-about 70,000, versus nearly 600,000 for the iPhone and more than 450,000 for Android. It also has a weaker content ecosystem. For instance, there is no way to buy TV shows or movies directly from the phone, and far fewer magazine and newspaper apps are available.

Casey Johnston, Ars Technica:

The new hardware can hold up against both of these more expensive phones, and Nokia's total package deserves to be taken seriously. Still, the OS has some maturing to do compared to [Android and iOS]. Power users for whom price is less of a factor will find much to admire here, but they still may not be won over when it comes to getting the best handset, period.

Edward Baig, USA TODAY:

The Lumia 900 I've tested runs Windows Phone version 7.5, or Mango. I like the hardware, and I like the operating system. Windows Phone is fresh and different from iOS and Android and offers a strong alternative to the status quo.

Sam Biddle, Gizmodo:

The specs are nothing singular, but this is one phone that will keep you from thinking about its specs. ... Windows Phone, as an OS, is fundamentally rectangular and minimal. That's its best aesthetic virtue. ... The augmented Lumia doesn't feel fattened, it feels broadened. It's an exquisite slab of super-responsive, clear glass and a bright, tough-as-a-brick body. Trust me! I tossed the 900 high into the air. It landed in a muddy field. It was fine. ... But back to bright. The whole phone is bright. The display absolutely sings. Colors are, for the most part, terrific and vivid, and blacks are blacker than I've seen on any handset. Text pops with legibility and photos are sharp and vivid. It's a pleasure to swipe across-you just want to keep touching that wide pixel plane-and LTE only makes the phone feel more likely to make you smile.

Kevin Tofel, GigaOM:

There's no perfect phone for everyone and there's still room for improvement in Windows Phone. Having said that, I anticipate that with heavy marketing and the relatively low up-front cost of the Lumia 900, AT&T will sell a fair number of these phones. ... With the Lumia 900, Nokia has proven - at least to me - that it can bring its design chops and hardware experience to compete against the iPhone and Android devices. The phone also illustrates that Windows Phone is a very competent operating system with a fast-growing ecosystem. Where it lacks in terms of application breadth, it makes up for with desirable Microsoft services. And AT&T gains a win for launching this hardware and software combo on its new LTE network. Plus it does so with fast HSPA+ fallback where LTE service is lacking.

Peter Pachal, Mashable:

I've been using the Lumia 900 for the past week, and it's a great smartphone. It's also an excellent example of just how far the Windows Phone platform has come since its debut a year and a half ago. Good Windows Phone apps used to be in extremely short supply, but I was pleasantly surprised to see many of the same apps that I use regularly on iOS in the Windows Phone Marketplace. Foursquare? Check. eBay? Check. Spotify? It's there. Readability? Yep. Kindle? Got it. Pulse? Totally. There's even Foodspotting, yo. Still, there's no Instagram, Pinterest, Flipboard or Hulu Plus. So the Marketplace - recently clocked at 65,000 apps to the iPhone's 600,000 - certainly has some catching up to do. But if you're not already locked into another platform, it's reassuring to know Windows Phone has the essentials covered.

Joshua Topolsky, The Verge:

I really wanted to love this phone. From a design standpoint, the Lumia 900 was immediately enticing. I'd already been salivating over Nokia's N9 and Lumia 800, so knowing that a slightly larger (but more feature packed) version of that device was headed our way was fairly encouraging. But while the hardware - at least externally - delivers, the phone as a whole does not. ... My annoyances aren't just about the color choices in the calendar, they're about whether or not scrolling in apps functions as it should, or if I'll get important updates in the background. Can I use IRC without breaking my connection every time I leave the app? How many steps does it take to get to the information I need? Do webpages display properly? Will the apps I need or want to use make it to this platform, and will they be any good when they get there? In some ways, I feel like I'm reviewing a webOS device again (but with much, much nicer hardware). There are all these wonderful ideas at play, but it's impossible to look past the nagging bugs and missing features.

Hayley Tsukayama, The Washington Post:

Love your iPhone? Love your Android? This probably isn't for you. Windows Phone is an interesting platform that may still have a chance to grow into something extraordinary, but if you're switching from either iOS or Android, you're going to notice some serious gaps. ... [But] if you're in the market for a new smartphone, aren't impressed with Android or Apple, this is worth consideration - especially for $99. The phone is also particularly good for Microsoft fans who already use Bing or SkyDrive on a regular basis and would like to have those integrated, by default, into their phones.

Steve Kovach, Business Insider:

The Lumia 900 boils down to two glaring problems: the screen resolution is horrible by today's standards and the Windows Phone 7 software suffers from a handful of fatal flaws, most notably the poor selection of apps. But at just $100 with a two-year contract from AT&T, you're getting a decent deal, especially considering the Lumia 900 is a 4G LTE phone.

Matthew Miller, ZDNet:

Windows Phone devices don't have the highest specifications, when you compare them to Android devices, but the great thing is specifications don't matter too much on Windows Phone. The OS flies even on my 1.5 year old Dell Venue Pro and HTC HD7 so you can really forget about the processor speed and RAM. The display is gorgeous and if I had anything to say about what I would like to see in the future it would be higher resolution devices. After using the HD display on the Samsung Galaxy Note and iPad 3 it is tough to go back to 800×480 pixels.

Joseph Volpe, Engadget:

While we wouldn't color this AT&T debut as a failure, we wouldn't call it a crowning achievement either. Apart from a stated preference and dedication to Microsoft's Windows Phone OS, savvy geeks on the cusp of the next best thing won't necessarily want what the 900 has to offer, especially in light of that other spotlight-stealing flagship, the One X. By no means are these phones on equal footing. It's just that Nokia may have shot itself in the foot, succumbing to the hazards of hyperbolic quicksand far ahead of launch day. Much ado about nothing? Not quite, the Lumia 900 has its strengths, coming mainly in the form of optics, but it's the overall package and performance that's simply too plain, too ordinary, too dependable to merit the haughty flagship halo it aspires to emanate.

Are you excited for the Lumia 900? If you were going to buy the phone for only one reason, what would it be? Let us know in the comments section below.