Correct - depending how the chat is started, a non-imessage number cannot be added. I think it has to do with having one number of the group that is apple id ba

Correct - depending how the chat is started, a non-imessage number cannot be added. I think it has to do with having one number of the group that is apple id based and not phone number based. So it is not about the color, but literally about being locked out of the conversation unless you are on an apple device. Edit: yes agreed that an Android app for iMessage would be perfect. And I'm fine with requiring an apple id. And I'm even fine with the color! But the sometimes it works and sometimes it doesn't is ridiculous.