hello, sorry for the late response. I think you are confused because IMS is the subsystem that gives us Voice in the LTE or NR networks, not need to be on iphone to use IMS, in fact when you phone supports VoLTE on your ISP you are using the IMS server. So IMS works on iPhone and many android phones. The question here is if samsung specifically supports SMS over IMS server in general and if I can check the status with some hidden code. In fact in Iphone I can see that in settings page, if the iphone show voice and sms you are sending sms over IMS too.. but IMS is used by android too.