To use Handoff features, you need to have all your devices set up with the same iCloud account. You can go to Settings -> General -> Handoff & Suggested Apps to make sure you have the feature enabled. Also enable Bluetooth if you haven't already, under Settings -> Bluetooth (or turn it on from Control Center). You'll need to have the two devices each other because Handoff works over Bluetooth LE (Low Energy).
Once all that's ready, here's the current list of announced apps from Apple that can be handed off:
- Safari
- Pages
- Numbers
- Keynote
- Maps
- Messages
- Reminders
- Calendar
- Contacts
There are hooks in iOS 8 that allow developers to build Handoff into their own apps, but so far there don't seem to be many available. For our example we'll stick with Mail. It used to be the old way was to create a draft, close it, choose “Save Draft” from the prompt, wait for it to sync, then go to the other device, launch Mail, go to the mailbox, then Drafts, then resume. Now you only need to have the other screen nearby. First, start your message (I started on my phone and switched to my iPad):
Composing an email on an iPhone. Yes that is my email signature.
Then go to your iPad, and behold the lock screen. It has a little icon in the corner with an envelope on it:
Email handoff icon on an iPad. Image by Louie Mantia.
Swipe up on the icon, and as if by magic, that same message is now waiting for you to finish on your other device:
Composing Handoff email on iPad. Right where I left it!
Another common scenario is needing to type a lengthier reply in Messages. You get the same process with a slightly different icon in the corner. If you need to use the bigger keyboard to type your reply, this is an easy way to do so (particularly if you don't have your Mac with you). And it's much quicker (in my informal testing) than unlocking the iPad, launching Messages, waiting for it to catch up from the last time you opened Messages, then finding the right message thread and composing. With Handoff, a swipe up and if necessary about a second of delay to show the right thread, and you're off to the races.
When Yosemite is added to the mix, it will be even more convenient to start on one screen and finish on another, regardless of the task. For now, it's a pretty major improvement for folks who spend a lot of time on their iOS devices.