I received a call today, and the Handoff box popped up on my screen as usual. I took the call on my phone and the box disappeared.
Then, partway through the call, I wanted to "hand off" the call back to my computer. But I couldn't figure out how to do it, and the Apple help page wasn't very clear.
How can I take a call on my iPhone and then pass it to my MacBook? I'm running iOS 9 on an iPhone 6S, and OS X El Capitan on a MacBook Pro retina -- so I know my hardware is capable of it.