Handoff is Apple’s continuity feature, which allows you to start working or using a tool on one device and seamlessly pick up on another, whether it’s from iPad to iPhone or Mac to iPad.
To use Handoff, you must be signed in to the same Apple Account on all devices, connected to the same Wi-Fi network, and if you want to Handoff to a Mac, it must be running macOS Yosemite or later.
Here’s how to set it up: go to Settings, tap General, then AirPlay & Handoff, and toggle the Handoff option to on.
To use it, start working on a device, then pick up your iPad. If the app you were using can be handed off, its icon will appear at the right-hand end of the Dock. Tap it and the app will open where you left off. (On iPhone, you’ll find the option at the bottom of the App Switcher.)
On iPadOS, you can Handoff via Mail, Safari, Maps, Messages, Calendar and more, while a number of third-party apps like Google Chrome also support Handoff.