When RCS messaging became available on the iPhone with the rollout of iOS 18, the technical director of the GSM Association teased that the next major milestone for the messaging standard is the addition of interoperable end-to-end encryption.

With the GSMA releasing new RCS specs, Apple pledges to 'add support for end-to-end encrypted RCS messages to iOS, iPadOS, macOS, and watchOS in future software updates.'

Apple finally brought RCS messaging to iPhones with the release of iOS 18 in September of 2024. However, it wasn't perfect as end-to-end encryption wasn't available between iPhones and Android devices. In December, the FBI warned Apple and Android users to avoid RCS messaging because of the missing encryption.