Operating-system announcements often focus on what users will see. For developers, the more consequential question is what can be built reliably. Huawei's HDC 2026 materials describe HarmonyOS 7 capabilities around agent frameworks, cross-device interaction, space computing, security, and performance. Those features will matter only if the development tools make them testable and the documentation makes their limits clear.
The cost of a new capability
An API is not finished when it can produce a demo. Developers need versioned documentation, sample projects, simulator support, debugging tools, performance guidance, and a clear compatibility matrix. They also need to know what happens when a device lacks a sensor, a network connection drops, or a permission is denied.
Agent features raise the bar because they combine model behavior with application state. A developer must test not just the successful path but also ambiguity, partial completion, duplicate actions, and user cancellation. Good tooling should make those cases visible instead of hiding them behind a polished interface.
One codebase, many devices
HarmonyOS's cross-device proposition can reduce duplicated work, but multi-device support introduces its own testing matrix. A phone, tablet, PC, watch, and smart-home device have different screen sizes, sensors, battery budgets, and privacy expectations. “Develop once” is valuable only when the platform also makes adaptation practical.
The durable competitive advantage for HarmonyOS will be developer time. If the beta turns ambitious system features into stable, inspectable building blocks, the ecosystem can grow beyond headline numbers.