Apple is starting to test end-to-end encrypted (E2EE) RCS messages with the developer beta of iOS 26.4 released Monday. Apple announced plans last year to support the feature, and once fully available, it will let iPhone and Android users send encrypted RCS messages to each other across platforms.

However, with this initial implementation, Apple is only testing RCS encryption between Apple devices. It’s “not yet testable with other platforms,” Apple says. The company also doesn’t plan to ship E2EE RCS messages with iOS 26.4; the feature will actually ship publicly in a “future update,” Apple says.

RCS messages significantly improve the experience of texting between iPhone and Android devices, but cross-platform encryption has been a big thing missing. The GSM Association, which helps develop RCS, announced in September 2024 that it was working on E2EE messages as part of the “next major milestone” for the RCS Universal Profile, and Apple said in March 2025 that it would support E2EE RCS messages on iOS, iPadOS, macOS, and watchOS in “future software updates.”