How to set up and activate iMessage for iPhone and iPadHere's how to set it all up in iOS 12.
iMessage lets you send and receive SMS-like text messages, and MMS-style multimedia messages just like a phone through your iCloud account. Instead of a just a phone number, however, it can use your email address, and it only works with other iPads, iPhones, and Macs. Before you can start using iMessage, you'll need to set it up; here's how you do it!
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How to activate iMessage for iPhone or iPad
If you set up your iPhone using iCloud, chances are iMessage was activated along with it. If not, or if you ever need to re-activate it, it's simple to do!
Launch Settings From your home screen.
Tap Messages.
Tap the iMessage On/Off switch. The switch will be green when it's been turned o...
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How to set up and activate iMessage for iPhone and iPad