I run cyanmod m11 d2lte for i747 okay and we ran with a bill of 200+ and now switching to sprint is there a way to make this rooted phone switch providers?
So switch the service from at to sprint
An AT&T S3 has GSM radios. A Sprint S3 would have CDMA radios. So you can't use that phone because it won't work on Sprint's towers. I think, also, that Sprint won't allow you to use a phone that's not theirs on their network (I don't think they have a "bring your own device" plan), so you couldn't do it even if the phone would work on their towers.