A quarter of a million Droid handsets were sold in the first week after the Motorola smartphone from Verizon Wireless was released Nov. 6, according to a new estimate by mobile app analytics firm Flurry.

That makes the much-hyped Droid easily the bestselling Android-based phone to date, far surpassing the opening week performance of the T-Mobile myTouch, which sold 60,000 units. In comparison to the latest iPhone model, however, the Droid's debut was not quite as impressive. The iPhone 3G S sold 1.6 million in its first week in June.

But Flurry pointed out the upgraded Apple device was launched simultaneously in eight countries and that the iPhone already had an installed base of 25 million when the 3G S hit stores. "Taken in this context, Droid sales of 250,000 units during its first week from a standing start and in just one country, is a strong result for Motorola and Verizon," Flurry wrote in a blog post.

Equity research firm Broadpoint AmTech estimated last week that Verizon had sold about 100,000 Droids in its first weekend, or about half the amount it had in stock at launch. The original iPhone is estimated to have sold 240,000 at launch.

With Motorola forecasting Droid sales of 1 million by year's end, Flurry estimates a cost per acquisition of $100 per handset sold, based on the $100 million ad campaign Verizon is running to promote the device. "Verizon's aggressive campaign coupled with its 3G network advantage in key, populous regions of the country like the Northeast positions the Droid as a legitimate challenger to the iPhone," stated the firm.

Flurry also reported that Android continues to have an advantage over the iPhone in app usage, with people using Android apps for an average of four minutes per session -- twice that of the iPhone. The App Store's selection of 100,000 apps, however, still dwarfs the Android Market's 12,000.

Through its analytics service, Flurry monitors use of over 10,000 apps on the iPhone and Android phones, amounting to tracking across two-thirds of both types of handset.

To estimate first-week sales for the myTouch, Droid and iPhone 3GS, the company tracked new handsets within its system, and then made adjustments to account for different levels of app penetration by handset. It also cross-checked estimates against actual sales for the 3GS, which sold 1 million units in its first three days.

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