I remember before the release of the iPhone, you could send SMS text from your Mac. You could also use your Mac as a caller id with bluetooth sync to your mobile device Right before the release of the first iPhone, Apple removed it. So I see now Yosemite is bringing it back. I wonder why Apple took so long to bring it back. More pressing question is why would you remove it? This is screen shot I took back in 2008. This was a feature in Address Book. All you had to do was sync your mobile phone via bluetooth.