I was wondering if republic wireless would be carrying iPhones any time in the near future
while I never say never I would not expect iPhones any time soon,
Apple keeps iOS lock down and has not published the need API (if it even has them for 3rd party developers) for VOIP though the native dialer which is why Republic is supporting phones with Android 6.0+ as it has the need API and is published as Android is an Open system(the legacy phones need to Custom ROM build of Android due to the need API did not exist in a way for Republic to use before 6.0
As of iOS 10, Apple does indeed publish APIs that make it possible for Over the Top (OTT) Voice over Internet Protocol (VoIP) apps to behave more like native mobile phone service: Opinion: Does integrated VoIP support in iOS 10 signal the beginning of the end for voice plans? | 9to5Mac. I don’t believe it’s yet enough to bring Republic’s blended WiFi/cell technology to iOS but I do believe we’re getting closer. That said, I agree with your assessment that it’s likely to be longer-term as opposed to short to medium term.