Handoff is one of the headlining features of both iOS 8 and OS X 10.10 Yosemite. Part of a broader approach to bring Continuity to Apple devices, Handoff allows you do things like start composing an email on your iOS device, switch to your Mac, and continue composing it with a couple of clicks.
No more saving a message to drafts and waiting for it to sync over to your Mac. The same type of functionality carries over from Maps, Safari, Messages, Contacts, Calendar and Reminders.
After you upgrade to Yosemite, Handoff should be enabled by default. But it's a good idea to confirm.
- Launch System Preferences from your Application folder.
- Click General.
- At the bottom of the panel is a checkbox titled "Allow Handoff between this Mac and your iCloud devices."
- Check the box if it's currently empty.
Now that you've verified that Handoff is enabled, anytime an Apple device that shares the same iCloud account is connected to the same Wi-Fi network, you'll be able to seamlessly switch between them.
When it's possible to launch an app or service, an app icon complete with a device thumbnail will display next to the Finder icon on your Mac's dock. You only need to click on the icon to open the respective app on your Mac.
Handoff is a two-way street, too, meaning you can switch from a Mac to an iOS device, a Mac to a Mac, or just as easily switch between iOS devices.
And as third-party developers begin to take advantage of the new feature, we can expect to see more interesting use cases. If you're reading a Vice News article on your Mac and you have the ViceNews app installed on your iPhone, an icon for the app will display on your phone's lock screen. Sliding up on the icon launches the app directly to the story you were reading on your computer.
Should you run into any issues getting the service up and running, go back to the settings page mentioned above and disable Handoff. Then after a few seconds, re-check the box and try again.
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