One of the newest features of Yosemite and iOS8.1 is the ability to use a function called handoff. This service allows you to continue working on one device where you left off on the other. The app must be handoff capable and the settings must be set up. It should happen automatically when your devices (Mac and iOS) are signed in to the same iCloud account. You can learn more about the continuity feature from Apple.
To use the service, your Mac must be updated and running Yosemite. Your iOS device must have 8.1 installed. Both your Mac and iOS device must have the version 4.0 of bluetooth. Your iOS device iPad third generation and after and iPhone 4S and after have the required bluetooth capability. To determine if your Mac has the proper Bluetooth level required, select the Apple > About This Mac > System Report and click on Bluetooth. If 4 or greater appears, Handoff should work.
Make sure hand off is checked on your Mac by going to System Preferences > General and Check “Allow Handoff between this Mac and your iCloud devices”
Then, you will be able to use the function with your iOS device.
Making Phone Calls
According to Apple, “You can make and receive phone calls on those devices as long as your iPhone running iOS 8 is on the same Wi-Fi network. Incoming calls show the caller’s name, number, and profile picture. Just click or swipe the notification to answer, ignore, or respond with a quick message. And making a phone call from your iPad or Mac is just as easy. Simply tap or click a phone number in Contacts, Calendar, or Safari. It all works with your existing iPhone number, so there’s nothing to set up.”
Handoff promises to be a helpful feature in allowing you to seamlessly work between your various iOS devices and your Mac.