Prior to iOS 8, if you started to compose an email on your iPhone, only to decide you want to finish it on an iPad or Mac, you'd have to save it to your drafts. Then you'd need to wait for it to sync to your online account, then back to your iOS device, where you can then pickup where you left off. With iOS 8 that all changes.
What is Handoff?
With iOS 8, Apple is introducing a new feature called Handoff. By linking all of your iOS (and eventually OS X) devices using a common iCloud account, you can seamlessly switch between devices without losing any work or having to wait for servers to sync content.
In addition to Apple's Mail app, Handoff also works with Messages, Safari, Reminders, Contacts, Maps, Keynote, Pages, Numbers, and Calendar. And for those developers who opt to integrate the feature into their apps, Handoff will allow for the same continuous access to information between multiple devices.
The feature is enabled by default after you update your iOS device(s) to iOS 8, but should you run into trouble with getting it to work, you can find its control switch in iOS Settings > General > Handoff & Suggested Apps. Toggling a feature off then back on is always a good starting point for troubleshooting.
Switching between devices
OK, all of that sounds nice, but how do you use it? Well, once your devices are all synced up (it can take some time after upgrading to iOS 8 for this to happen) you will begin seeing compatible app icons appear on your lock screen or as an extra pane in app switcher. The icons will directly relate to whatever app you're using. Sliding up the app icon from the lock screen, or selecting the pane in the app switcher, on your secondary device will launch the app.
Calls and SMS
Additionally, phone calls will begin showing up on your iPad, where you can then answer and talk as if you were on your iPhone. You can place calls from your iPad using the "Audio" pane of the FaceTime app, or by tapping on a phone number in the Contacts app.
The ability to compose and reply to SMS messages from your iPad and Mac is yet another feature of Apple's Continuity initiative, but it doesn't appear it's quite ready yet as Apple's site states it will be available in October. When it does go live, however, a prompt will ask if you want to grant a device access to your iPhone's SMS messages. Saying yes will result in SMS messages showing up in the Messages app on both OS X and iOS.
It's important to note, for calls and SMS to work, your devices will need to be on the same Wi-Fi network.
At first I didn't think Handoff was going to be something I used often. Sure, it sounded good in theory, but was it going to be practical? After using it throughout the beta process, I have found myself using it more and more. It has become part of my workflow, as I no longer feel like I have to limit myself to performing certain tasks on certain devices. With iOS 8, I know I can finish nearly any task on another device if need be.
For more helpful iOS 8 tips, be sure to check out our complete guide to iOS 8.