[oniro-wg] 2026 Proposal 3 future plans: Integration of Universal RCS Su

[Benjamin Akhigbe <benjaminakhigbe@xxxxxxxxx>]

Dear Oniro Working Group Members,

Integrating Rich Communication Services (RCS) support is a strategic move that significantly enhances the 2026 final proposal's completeness and modern relevance. 

Integration of Universal RCS Support

This final proposal, proposes integrating the open-source rust-rcs-client into the unified Oniro/OpenHarmony developer platform. The goal is to provide a standardized, secure, and device-agnostic API for developers to incorporate advanced messaging features (chat, file sharing, read receipts, typing indicators) directly into ArkTS/Cangjie applications.

1. Strategic Rationale for Inclusion

Fills a Critical Communication Gap: It provides a modern, IP-based alternative to SMS/MMS, aligning the platform with global carrier standards (GSMA) and user expectations for rich messaging.

Enhances Application Capabilities: Empowers developers to build sophisticated communication features into social, productivity, enterprise, and customer-service apps without relying on third-party SDKs.

Strengthens Ecosystem Value: A system-level RCS service makes the platform more attractive to OEMs, carriers, and developers by offering a built-in, interoperable communication layer.

Alignment with Open Principles: Using a Rust-based open-source client (rust-rcs-client) perfectly aligns with the proposal's core philosophy of leveraging secure, performant open-source components.

2. Proposed Technical Integration Architecture

The RCS client would be integrated as a system service, accessible via a unified API:

Key Components:

RCS System Service: A daemon process wrapping the rust-rcs-client logic, managing network connections, encryption, and message queueing.

Standard Messaging API: A new, well-documented API module within the proposed cross-platform framework (e.g., Open Mobile Hub), exposing functions for messaging, group chat, and file transfer.

Security Layer: Integrates with the platform's core security measures for user authentication, end-to-end encryption (using the client's built-in support), and strict permission controls for apps accessing messaging functions.

3. Analysis of the rust-rcs-client Project

Feasibility & Fit: The project is implemented in Rust, making it an ideal candidate for system-level integration due to its memory safety, performance, and cross-compilation support (relevant for phones to wearables).

Integration Path:

Upstreaming: Propose adopting and maintaining the rust-rcs-client within the Oniro Working Group to ensure long-term alignment and support.

Adaptation: Develop a lightweight "adapter" or "binding" layer (in Rust or via C-ABI) to allow the ArkTS runtime to communicate with the RCS client service.

Toolchain Support: Ensure the BiSheng compiler toolchain can seamlessly build the Rust components alongside native C/C++ code.

4. Benefits to the Original Proposal

For Developers: Simplifies adding carrier-grade messaging. They can use a single, standard API instead of navigating multiple proprietary SDKs (e.g., for different regions or carriers).

For End Users: Guarantees a consistent, secure, and high-quality messaging experience across different applications and devices (phone, tablet, PC) within the ecosystem.

For the Platform: Creates a unique selling point versus other OS ecosystems where RCS implementation is often fragmented or controlled by a single app.

5. Challenges and Considerations

Challenge Mitigation Strategy

Carrier Interoperability The rust-rcs-client must be rigorously tested and certified with major RCS hubs (like Google Jibe). This requires collaboration with carriers.

System Resource Management The RCS service must be optimized for battery life and network usage, especially on wearables. Rust's efficiency helps, but careful power management is needed.

Regulatory Compliance The implementation must adhere to regional regulations (e.g., GDPR, local data sovereignty laws) for message handling and storage.

Conclusion

Adding standardized RCS support via the rust-rcs-client transforms the proposal from a foundation for general applications into a truly competitive, communication-ready platform. It directly addresses a key modern use case, leverages a robust open-source component, and reinforces the core tenets of standardization, security, and cross-device/platform unity for OpenHarmony-based systems with Android and iOS.

This integration should be presented as a key module within the broader proposal's "Standard API" specification, positioning the Oniro/OpenHarmony stack as a forward-thinking, full-featured alternative in the global mobile ecosystem.

Best regards,
Benjamin Akhigbe
Learning Oniro/HarmonyOS UK/Global Developer
benjaminakhigbe@xxxxxxxxx