[Bellyache5]

Using iMessage requires an Apple ID. The Messages app on iPhones supports both SMS/MMS and iMessage because it’s a phone and needs to support SMS. But without being signed into an Apple ID on the device the Messages app only handles SMS/MMS, i.e., green chat bubbles.

[selectodude]

That isn't true. You can use iMessage without an Apple ID on a phone. It uses your phone number. I promise you of this.

[tsimionescu]

Yes, but if you don't have an Apple ID, the iMessage app will use SMS/MMS, not the proprietary encrypted Apple messaging protocol. This can be tested easily: send a message to another Apple user: it will arrive as a green SMS message, not a blue Apple messaging message.

[philliphaydon]

iMessage without an appleid is just SMS…

[owly]

Promise all you want, but in the US you can’t activate an iPhone without an Apple ID. Yes, you can set iMessage to only send/receive iMessages using your phone number. However, you cannot set it up in the first place without an Apple ID.

[Godel_unicode]

https://www.macworld.com/article/673831/how-to-use-an-iphone...