Handoff is the feature on Apple Watch and iPhone that allows you to start a task on one device and finish it on another. For example, you might check email on your watch and then switch to your phone to compose a reply.
移交是Apple Watch和iPhone上的功能，可让您在一个设备上启动任务并在另一设备上完成任务。 例如，您可以在手表上查看电子邮件，然后切换到手机以撰写回复。
You must use your iPhone to enable the Handoff feature on your Apple Watch. Tap the “Watch” app icon on your phone’s Home screen.
您必须使用iPhone在Apple Watch上启用“切换”功能。 点按手机主屏幕上的“观看”应用程序图标。
Make sure the “My Watch” screen is active. If not, tap the “My Watch” icon at the bottom of the screen.
确保“我的手表”屏幕处于活动状态。 如果没有，请点击屏幕底部的“我的手表”图标。
Tap “General” on the “My Watch” screen.
在“我的手表”屏幕上点击“常规”。
On the “General” screen, tap the “Enable Handoff” slider button to turn on the feature. The button turns green when it’s enabled.
在“常规”屏幕上，点击“启用切换”滑块按钮以打开该功能。 启用后，该按钮变为绿色。
Now, you can perform a task on your watch, such as viewing an email message.
现在，您可以在手表上执行一项任务，例如查看电子邮件。
Then, you can access your iPhone to see an email icon in the lower-left corner of the lock screen. Drag up on the icon.
然后，您可以访问iPhone并在锁定屏幕的左下角看到电子邮件图标。 向上拖动图标。
You may be prompted to enter your passcode to access your phone, but once you log in the email you were reading on your watch displays on your iPhone screen.
可能会提示您输入密码以访问手机，但是登录电子邮件后，您正在阅读的手表会显示在iPhone屏幕上。
Handoff works with Mail, Maps, Messages, Phone, Reminders, and Calendar, and Siri. Your Apple Watch must be in close proximity to your iPhone for the Handoff feature to work.
越区切换适用于邮件，地图，消息，电话，提醒和日历以及Siri。 您的Apple Watch必须与iPhone靠近，才能使用“切换”功能。
Handoff is part of the technology called Continuity that allows you to transfer tasks among your iOS devices and your Mac. Continuity also includes Phone Call Forwarding, Text Forwarding, and Personal Hotspot.
移交是一项称为“ 连续性 ”的技术，该技术使您可以在iOS设备和Mac之间传输任务 。 连续性还包括电话转接，文本转接和个人热点。
翻译自: https://www.howtogeek.com/236321/how-to-enable-handoff-on-your-apple-watch/