Microsoft has a history of tenaciously pursuing a market once it sets sights on a target. Take the 1990s browser wars, for example. Or the continuing Xbox versus PlayStation saga. 

Although it often enters as a latecomer and underdog, Microsoft accomplishes some impressive feats when its back is against the wall. That's a perfect description of the mobile market right now, as Android seems unstoppable and iOS commands a strong second place.

But did you know that Microsoft surpassed Blackberry's market share in 2013, and shipped more than 10 million devices in Q4 of last year? Or that Windows Phone doubled its global smartphone OS market share in Q3, to just under one-third of Apple's? 

Now that it owns Nokia, there's little reason to believe that Microsoft will not do everything in its power to continue this momentum. And if you doubt its conviction, the software giant recently announced that it will drop the Windows royalty fee for devices with screens below nine inches. Perhaps it's a bit early to crown Android the victor in the battle for smartphone supremacy.

While Windows Phone 8 took big strides in the budget sector on Nokia's Lumia 520 (a phone that offers fantastic value on a pay-as-you-go basis), most of us wouldn't aspire to own one. Nokia has a cutting-edge phablet (phone/tablet) in the Lumia 1520, but that form factor isn't for everyone. 

Windows Phone needs a flagship to prove it can compete against the Google Nexus, Samsung Galaxy, and HTC One. It needs something in the 5" display category. Its answer arrives in the Lumia Icon, also known as the Nokia Lumia 930 to non-Verizon customers.

Given a strong spec sheet, the Icon/930 earns a position in the same tier as other high-end Android-based devices. Quad-core Qualcomm Snapdragon 800 at 2.2 GHz, check. Adreno 330 graphics engine, check. Two gigabytes of LPDDR3, check. 

LTE support, check. Five-inch AMOLED 1080p screen with an impressive 441 ppi, check. Forward-looking 802.11ac wireless support, check. Twenty-megapixel camera, check. And although you don't get microSD expansion, 32 GB of on-board storage is nothing to sneeze at.

If those specifications look familiar, that's because the Icon and 930 share almost all of them with Nokia's Lumia 1520, which differentiates itself with a larger 6" IPS LCD display and memory card support. 

But again, a 6" screen classifies the 1520 as a phablet. In reality, the Icon/930 is more of a successor to the Lumia 1020, which could be considered the previous flagship Windows Phone device.

The Lumia Icon/930 improves upon its predecessor's specs in every way, except for imaging hardware. The Lumia 1020's xenon flash and 41 MP camera remain the tops optics in the smartphone industry, while the Icon employs a better-than-average 19.66 MP camera with a large 1/2.5" sensor and dual-LED flash.

For what it's worth, that's also what you'll find in the Lumia 1520. And although the sensor doesn't sound as impressive as the Lumia 1020's, you also don't have to deal with a protruding bump on the Icon's chassis, either.

When you compare the Icon/930 to a contemporary device like Google's Nexus 5, the playing field narrows considerably. Both feature similar quad-core Qualcomm Snapdragon 800 SoCs, even if the Nexus' CPU cores operate at up to 100 MHz faster. The two phones similarly come equipped with Adreno 330 graphics, too. While both these phones have 5" 1920x1080 displays with 441 ppi pixel densities, the Nexus employs an IPS LCD compared to the Icon's AMOLED screen, giving Nokia an advantage in contrast levels and power usage.

Speaking of power, the Icon/930 has a slightly beefier 2420 mAh battery. And though Lumia's 19.66 MP camera is a downgrade from the 1020, it certainly looks good on paper next to the Nexus 5's 8 MP sensor.