Here’s a crazy new feature in OS X Yosemite, the Mac’s latest operating system: You can see what’s happening on your iPhone or iPad on the Mac’s screen, where it’s much bigger and clearer. It’s a great way to show what’s on your screen to a classroom or an auditorium, if your Mac is connected to a projector. This tip also makes it super easy to record what’s on your iPhone or iPad.
Here’s how to do it: Connect the iPhone or iPad (with its white USB cable) to the Mac. On the Mac, open QuickTime Player. From the File menu, choose New Movie Recording. And then, from the pop-up menu next to the Record button, choose the iPhone’s name (or the iPad’s). The phone/tablet’s image appears in the QuickTime Player window, nice and big.
Now you can show your phone activity to a crowd, or even hit Record to record it as a movie.