Fitness wristbands that work across multiple mobile OSes aren't new: the Fitbit, Pebble, Jawbone, Nike and others also play well with different smartphone platforms, fitness apps and notification services. But Microsoft's entry is especially noteworthy given the companies history, size and recent struggles to sell tablets.
One theory regarding the limited supply is that Microsoft was being cautious after losing more than $1 billion on its Surface tablets. "Microsoft was burned with the write-down on Surface, so I think they were very conservative on the builds for Band," said Patrick Moorhead, an analyst at Moor Insights & Strategy.
Another factor: The company may be trying to get ahead of the upcoming Apple Watch, which is due to arrive in early 2015, and Apple's HealthKit software, and fend off other new smartwatches and smart wristbands, such as the Intel MICA and the Samsung Gear S.
"Microsoft has been late in the past with new form factors like the touch-based tablets and smartphones, which put pressure on them to not to be too late with a fitness device," Moorhead said. "Therefore, Band was developed to show that they weren't that late, but also to show off their new Health platform."
Ironically, the recent explosion in the number of new smartwatches and fitness wristbands could help Microsoft -- if users connect their new devices to Microsoft Health.
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