iPhone trying to send message as iMessage to non-iOS recipient
When I create a new message, I select the contact (who has a non-iOS device, in this case a Samsung Galaxy), the contacts name is green, which is fine.
When I select the green contact's mobile number, the banner at the top goes from "New Message" to "New iMessage", the name stays green, but after typing a message the "Send" button remains greyed out so I cannot send it.
I don't know why the iPhone is trying to send this as an iMessage when it clearly knows full well that the recipient is non-iOS (as the contact name is green).
I have an iPhone 4s on iOS 7.1
iPhone 4S, iOS 6