So I have a Samsung s21 ultra phone but I recently got a MacBook air and sent a text to a friend who has an iPhone. When they responded to the text, my phone didn't receive it but the mac continues to. How would I fix this? Or is this irreversible?
MacBook Air (2020 or later)
iPhone to Mac uses iMessage, a proprietary Apple service designed to work exclusively with Apple devices. Your Samsung phone cannot use iMessage, but it can communicate with iPhones using SMS / MMS text messages, just like any other phone.
What is the difference between iMessage and SMS/MMS? - Apple Support
Note:
"You can also set up your other Apple devices to send and receive messages from any Apple device."
... the important part being Apple devices.
iPhone to Mac uses iMessage, a proprietary Apple service designed to work exclusively with Apple devices. Your Samsung phone cannot use iMessage, but it can communicate with iPhones using SMS / MMS text messages, just like any other phone.
What is the difference between iMessage and SMS/MMS? - Apple Support
Note:
"You can also set up your other Apple devices to send and receive messages from any Apple device."
... the important part being Apple devices.
Messages
