I use iMessage with a lot of international contacts (Friends and family) since it is free. Is there a way to set certain contacts in the Messages app to be iMessage only? When the signal or data is bad on either end, it sends the messages as text messages which ends up costing quite a bit if it happens a lot. I would like to set my International iMessage contacts so that if the signal or data is bad, instead of sending a text message, it just stops working until it gets better. Is this possible?