The smartphone industry is on fire, as you might have noticed. Research firm Gartner has released a report on the state of the industry. In Q1, Nokia reigned supreme with over 100 million device sales. Samsung was also extremely strong with 69 million units, while Apple moved 17 million units (that’s a doubling of sales year over year), and HTC and Motorola did very well, selling around 9 million units each. If you look at how this breaks down by operating system, Android units sold the best at 36 million units, while Symbian came in second at 27 million, and Apple third at 16 million. Lagging a bit behind was Microsoft, selling an estimated 3.6 million units, of which 1.6 million were Windows Phone 7, and 2 million were devices running on legacy Windows Mobile. Certainty this isn’t an apples-to-apples comparison, since Android, iOS, and certainly Sybmian have been on the market for several years, while Windows Phone 7 began shipping a bit over six months ago. Still, it’s a telling sign that Windows Phone 7 has a bit to go before it gains enough momentum to make it truly competitive with the other heavyweights out there.