https://techcrunch.com/2017/09/18/apples-imessage-based-mobile-payments-service-wont-be-arriving-tomorrow-in-ios-11/

Apple’s upcoming iMessage-based mobile payments service, powered by Apple Pay, won’t arrive tomorrow with the release of the new operating system for Apple’s mobile devices, iOS 11. According to an announcement released today by the company, the service will instead ship in a later release to iOS 11 and watchOS 4, due this fall.

Apple didn’t give an exact time frame for that launch, but it was already expected that the feature would not be included in the updated OS tomorrow, given that Apple’s website had already flagged the Apple Pay service as “coming this fall,” as MacRumors has pointed out.