Even though Apple’s 2014 OS X update is compatible with many Mac models, including older machines dating back to 2007, not all the new features included in Yosemite can work on older laptops and desktop. One of the best additions to OS X, at least for users who also own iPhones and iPads, is Continuity/Handoff, but the feature only works on Macs that have Bluetooth 4.0 support, which means that Macs older than mid-2012 (depending on model) can’t support it.
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