# HarmonyOS NEXT

HarmonyOS NEXT (Chinese: 鸿蒙星河版; pinyin: Hóngméng Xīnghébǎn) is a proprietary distributed operating system and a major iteration of HarmonyOS, developed by Huawei to support only HarmonyOS native apps. The operating system is primarily aimed at software and hardware developers that deal directly with Huawei. It does not include Android's AOSP core and is incompatible with Android applications.
While discarding the common Unix-like Linux kernel, HarmonyOS NEXT also replaces the previous multikernel system with its own HarmonyOS microkernel. The rich execution environment (REE) version of HarmonyOS microkernel is placed at its core with a single framework as kernel mode. The new kernel architecture, built on OpenHarmony and its kernel abstraction layer, serves as user mode. The OS shares lineage with the lightweight LiteOS real-time operating system for resource-constrained devices like smart wearables and IoT products.

## HarmonyOS kernel

HarmonyOS Kernel (HongMeng Kernel), sometimes referred to as the Harmony kernel, is a computer operating system (OS) kernel developed by Huawei since August 2023. It is used in the HarmonyOS 5 version of the proprietary HarmonyOS distributed operating system, replacing previous versions that utilized the AOSP compatibility layer, the Linux kernel, and the LiteOS kernel.
The HarmonyOS Kernel utilizes a microkernel architecture, which aims to improve security and performance by isolating critical components of the system.

### Kernel design

HarmonyOS kernel is a microkernel at rich executed environment level for software outside hardware-based HarmonyOS TEE kernel, called tee_OS, enabling greater modularity and larger portions of the OS to benefit from memory protection at kernel mode. While retaining the speed of monolithic mainline Linux kernel compatibility subsystem of modular OpenHarmony standard system within its kernel abstraction layer as compatibility layer with POSIX APIs and third-party musl-libc integrated support for bigger advanced devices for some critical tasks at user mode of HarmonyOS operating system commercial distro. The kernel has Linux ABI compatibility by placing an ABI-compatible shim in IC0 (kernel space) with support for OpenHarmony and AOSP complex framework hardware migration deployments, which redirects Linux system calls to IPC and serves as a central repository for global state. The kernel also reuses Linux drivers through driver containers, which balances between compatibility and critical path performance, while having control plane and data plane separation to improve performance. HarmonyOS kernel capabilities in context switching, network, application startup time, load, frame loss, interrupt latency, etc., and also performance optimised in smart routers and smart vehicles with real time capabilities functions.
As of October 23, 2024, HarmonyOS kernel runs on ARM64 devices on HarmonyOS 5.0.0 Release (Beta) version with current version 1.9.3.B010.
HarmonyOS kernel offers core capabilities and security benefits to the upper layers, including process and thread management, memory management, file system management, network management and Peripheral management. Alongside, HarmonyOS kernel, the integrated Hardware Driver Foundation (HDF) underpins an open hardware ecosystem for HarmonyOS. It standardizes peripheral device access and streamlines I/O driver development and management. Other layers of the multi-layered operating system of OpenHarmony-based HarmonyOS that sits on top of HarmonyOS kernel includes the middle System Service Layer where the system service layer provides essential services enabling the framework layer to support application functionalities. It consists of several subsystems such as the Basic System Capability Subsystem set ensures seamless distributed operation across OpenHarmony devices by handling, Distributed app execution, Scheduling and migration, Core capabilities like Distributed Soft Bus (DSoftBus) around the Distributed Virtual framework across devices with distributed data management, Distributed Scheduler, Utilities, multimodal input, graphics, security, and AI. Also, Basic Software Service Subsystem Set: These subsystems offer universal software services such as for Common events and notifications, Telephony services, Multimedia handling and Design For X (DFX). Then, Enhanced Software Service Subsystem Set where these subsystems deliver specialized software services tailored for various device types, including Smart TVs, Wearables, IoT devices, personal computers, smartphones, smart car displays and other types of devices. Hardware Service Subsystem set provides hardware-related services such as, Location services, Identity and Access Management (IAM) and Services specific to wearables and IoT devices. These subsystems within the basic software, enhanced software, and hardware service sets can be adapted and extended to fit the deployment scenarios of different device forms. The framework layer equips developers with tools to create HarmonyOS applications. The core of the kernel is written primarily in a confined subset of C language. It includes, Application framework and ability framework, supporting multiple programming languages (e.g., C, C++, JS, ArkTS, Cangjie), ArkUI framework for user interface development, Multi-language APIs for integrating hardware and software services. These APIs can be customized to meet the requirements of different system components and devices. This upper level layer houses both system and third-party applications. Each native HarmonyOS HAP app that are interoperability with OpenHarmony user mode, utilizes one or more types of abilities: such as Feature Abilities (FAs) Provide user interfaces for interactive functionalities and Particle Abilities (PAs): Operate without a user interface, focusing on background processes and data access. Applications leveraging FAs and PAs offer distinct service features and enable cross-device scheduling and distribution, ensuring a consistent and efficient user experience.
The kernel features Address tokens that connects the Access token manager that is an essential component in OpenHarmony-based distributed operating systems, responsible for unified app permission management based on access tokens. Access tokens serve as identifiers for apps, containing information such as app ID, user ID, app privilege level (APL), and app permissions. By default, apps can access limited system resources. ATM ensures controlled access to sensitive functionalities which combines both RBAC and CBAC models as a hybrid ACL model.

## History

On August 4, 2023, at Huawei Developers Conference 2023 (HDC), Huawei officially announced HarmonyOS NEXT, the next version of HarmonyOS, supporting only native APP apps via Ark Compiler and native APIs in HarmonyOS SDK.
The kernel of HarmonyOS NEXT does not include the compatibility layer of AOSP framework with Android libraries from EMUI in the user space and cannot run Android apk apps natively, as is the case with the dual framework HarmonyOS.
The first internal preview version of the system was revealed on August 4, 2023, and the first preview version was released to registered public developers on January 18, 2024. The devices tested on the developer preview version of the system were the Mate 60, Mate 60 Pro, and Mate X5 phones in the first batch.
On October 22, 2024, HarmonyOS 5.0.0 was officially launched as HarmonyOS NEXT 5 brand, after the public beta released on October 8, 2024.

## Software version history

HarmonyOS Galaxy Edition (Star River) [5.0.0] (API version 12)
August 4, 2023 (API 9) Developer Preview 1 for HarmonyOS NEXT internal cooperative developers, for native software development. January 2024 Developer Preview 1 Beta for public registered developers (API 10), Developer Preview 2 (API 11–12), Q2 Beta (API 12), and Commercial (API 12) stable builds:
At the HarmonyOS Developer event in China, Huawei announced that the developer preview version of Harmony Next, the third generation of HarmonyOS operating system based on OpenHarmony L0-L2 branch source code, was open for application development, alongside the release of the beta version to enterprise developers on January 18, 2024. The beta version of HarmonyOS Next will be launched in Q2 of 2024 to all unregistered public developers, while a commercial version on specific devices will be released to all users in Q4 of 2024.

### Software architecture and framework features

* Native refinement of the system, application, fluency, security, intelligence, and native interconnection.
* Full-stack, self-developed HarmonyOS NEXT core operating system integrated that includes:
** Native AI LLM model: PanGu-Σ
** Native Generative AI framework: MindSpore
** Native Integrated Development Environment: DevEco Studio IDE and DevEco Testing
** Native Design system: HarmonyOS Design
** Native Programming framework: ArkUI / ArkUI-X (cross-platform)
** Native Compiler & Runtime: Ark Compiler, BiSheng Compiler and Ark Runtime
** Native File system: EROFS/HMDFS distributed file system
* Native in-house Cangjie programming language alongside ArkTS as primary programming languages support for native HarmonyOS system and kernel
* AOSP system and Linux kernel of EMUI system userland on System Service Layer removed from native compatibility on phones and tablets alongside some other devices via native OpenHarmony user mode.
* Primary HarmonyOS native app file package, APP for HarmonyOS apps only
* Native Package management subsystem
* Refined and primary native in-house Ark Engine multimedia API graphics stack system that comes with ArkGraphics 2D and ArkGraphics 3D with Cangjie support across all devices with developer access
* Linux and LiteOS RTOS base on wearables, phones, tablets on System Service Layer replaced with self-developed REE version of HarmonyOS kernel, Microkernel architecture.
* API 10, 11 features bundled
* New API 12 features
* HarmonyOS NEXT SDK with previous classic HarmonyOS SDK API levels, alongside full standard OpenHarmony SDK development kit access support conglomerated in a complete and comprehensive in-house HarmonyOS SDK API 12, in a form of full development kit.
* PC mode when keyboard used on MatePads and phone docked
* Native PC support
* Native HarmonyOS API apps adapted to PC support
* Native Generative Edge AI computing API system features for Edge Computing
* Native Generative AI and Multimodal learning LLM Voice Assistant Celia/XiaoYi [China & Global] - Powered by Huawei Pangu AI model, supports Chinese and English with Celia Proactive Suggestions and Developers can add Celia Voice services to their atomic services improvements and applications.
* Native device-side AI support for training interface and ArkTS interface for NNRt (Neural Network Runtime) backend configurations via MindSpore framework
* OpenHarmony versioning core baseline of HarmonyOS NEXT system versioning underlining the HarmonyOS operating system baseline versioning
* OpenHarmony user mode contains the kernel abstract layer that wraps the Linux syscall compatible layer via POSIX compatible, third-party musl from LiteOS lineage for HarmonyOS NEXT system kernel, in-house Microkernel.
* OpenHarmony Device Connector (HDC) native support, a command line tool for connecting and debugging HarmonyOS devices as well as OpenHarmony devices in interoperability, including self debugging on PC-side with native toolchain system. Replaces Android Debug Bridge on classic dual-framework OpenHarmony L3-L5 based EMUI and HarmonyOS AOSP userland base.
* Exclusive to in-house Kirin and HiSilicon chips optimisation and adaptation alongside selected Snapdragon legacy chips
* New visual graphical interfaces based on Neumorphism and Glassmorphism design language trend, visual elements on HarmonyOS Design language system for Spatial computing
* New Control Panel interface.
* New and refined notification and lockscreen interface.
* New volume control design.
* New native File and Photos picker app and interface.
* New bundled HarmonyOS native system apps.
* Native HarmonyOS settings app and OTA system
* Modified native Task Switcher interface for PC, phones, tablets and foldables
* Native smart app background and foreground management system
* Native developer and app kits support
* ArkData powered by GaussDB for ArkTS HarmonyOS native development
* New native AppGallery app designed for installation of native HarmonyOS apps only.
* WebView component based on the ArkWeb software engine.
* Next generation NearLink 2.0 support
* Native HMS Core integration
* New Permission application system with Capability-based security-like REE kernel features, alongside native OpenHarmony-based Access token manager implements unified app permission management on Core File Kit, departure from previous versions of HarmonyOS with AOSP framework
* Advanced native multitasking and Task switching system
* Native Push API system
* Continuity of applications between devices via native Distributed Package Management Service (DBMS) from Distribution Service Kit API.
* Spatial computing support
* Native Spatial Audio support in Audio Kit API
* Harmony Intelligence backend stack embedded across the OS, with PanGu 5.0 LLM with Embedded variant, MindSpore AI framework with Neural Network Runtime API kit with smarter Celia virtual assistant.
* AI body Feed upgrade of native Celia virtual assistant with analyzing documents, ask or summarizing. Also understand "this" and "that" according to context and information on the device. Also, AI voice fix for hearing aid and see world accessibilities in every scenario with AppGallery third party native full fledged apps and Meta enabled mini apps in SDK, API support, images, wallpapers for home and lockscreens on system etc.
* New Celia UI call from, holding gesture-based navigation bar to enlarge. Drag information into clipboard with text, photo, docs to Celia navigation bar for analyzing.
* Full scenario Intelligence OS
* Security accessible
* Star Shield security architecture
* Collaboration between apps with the New distributed soft bus, App hop, Cross devices gallery
* New upgraded Live Window with Lockscreen enhancements for native HarmonyOS apps integration, like delivery info, maps integrated with native Petal Maps APIs and third party mapping APIs technologies etc.
* Native Petal Maps includes Sequential Planning with Map Mode, Semi Modal
* Upgraded Desktop Mode for MatePad tablets and new Desktop PC systems for Matebook and MateStation PCs
* New split-screen interface
* New boot animation screen of HarmonyOS with OpenHarmony compatibility label of "Huawei" boot image
* Enterprise intelligent terminal management support
* New camera interface
* 30% performance boosts, 10.7% native custom HarmonyOS kernel performance boost compared former Linux kernel
* OpenHarmony compatibility test for existing and new devices
* 5.5G connectivity support with existing 5G, 4G in native telephony stack of OpenHarmony-based HarmonyOS NEXT
* Bluetooth BLE 6.0 support
* China local initial launch
HarmonyOS NEXT base compiled versions of its software versions in software development since August 4, 2023.
HarmonyOS NEXT releases :
| System version | OS version | Information | Release date |
| HarmonyOS NEXT (3.1) Developer Preview 1 [Internal Beta] | OpenHarmony 3.2 | HarmonyOS NEXT Developer Preview version equipped with latest base technology, open capabilities, and development kits. The new version comes with HarmonyOS kernel (Microkernel). Huawei Ark graphics engine added. Phones and tablets are tested. Native HMS Core built inside. Internally released developer only software on OpenHarmony base development stack with API 9. | August 4, 2023 |
| HarmonyOS NEXT (4.0) Developer Preview 1 [Internal Beta] | OpenHarmony 4.0 | New graphical shells, including PC and tablet PC mode support with API 10. | October 26, 2023 |
| HarmonyOS NEXT (4.1/4.1.1 - Canary Build) Developer Preview 1 [External Beta] | OpenHarmony 4.1 | A large number of ArkTS APIs have been added, and the scope of distributed hardware support has been expanded. Improved new graphical shells. PC APIs added. HarmonyOS Kernel (Microkernel) retrofitted on Canary1 builds with API 11. | January 18, 2024 |
| 2.0.0.59 (SP3DEVCC00E59R4P1log - Canary Build 2) | OpenHarmony 4.1 beta 1 | HarmonyOS NEXT Developer Preview 1 Beta rolled out on registered developers' handsets, Huawei Mate 60 Pro and other devices. | February 29, 2024 |
| 2.0.0.66 (SP3DEVCC00E59R4P1log - Canary Build 2) | OpenHarmony 4.1 | External preview beta expansion of Developer Preview 2 rolled out on more registered developers' handsets with latest pre-release canary build. | April 2, 2024 |
| 3.0.0.22(Canary3) | OpenHarmony 5.0 beta 1 | External beta expansion of Developer Beta 1 rolled out on more registered developers' handsets with latest pre-release developer Beta build with API 12. | May 25, 2024 |
| NEXT.0.026(SP6DEVC00E29R4P6log) Developer Beta 1 | 5.0.0.25(Beta1) | HarmonyOS NEXT Developer Beta 1 with API 12, "Full scenario" intelligence OS with Harmony Intelligence rolled out publicly to all registered developers June 21, 2024 at HDC 2024 annual event in China. | June 21, 2024 |
| NEXT.0.0.31 (SPXXXXXXXX) Developer Beta 2 | 5.0.0.33(Beta2) | HarmonyOS NEXT Developer Beta 2, expansion. | July 19, 2024 |
| NEXT.0.0.35(SPXXXXXXXX) Developer Beta 3 | OpenHarmony 5.0 beta 3 | HarmonyOS NEXT Developer Beta 3 expansion. | August 2, 2024 |
| NEXT.0.0.36(SP6DEVC00E38R10P8) - Developer Beta 3 | OpenHarmony 5.0 beta 3 | HarmonyOS NEXT Developer Beta 3 bug fixes and third developer beta recruitment extends. | August 7, 2024 |
| NEXT.0.0.60(SP12DEVC00E6QR4P9) - Developer Beta 5 | OpenHarmony 5.0 beta 5 | HarmonyOS NEXT Developer Beta 5 bug fixes and the final fourth developer beta recruitment extended. | August 21, 2024 |
| NEXT.0.0.65(SP3C00E65R1P6) - Beta 1 (Developer Beta 6) | 5.0.0.60(Beta7 API 12 release) | HarmonyOS NEXT beta recruitment for developers and early adopters expanded to more devices. First rolled out on three main devices for developer testing with API 12 transitioning with Developer Beta 6. | August 30, 2024 |
| NEXT.0.0.65(SP3C786E65R4P9) - Beta 1 | 5.0.0.65(Beta8 API 12 release) | HarmonyOS NEXT beta recruitment for developers and early adopters expanded to more devices. First rolled out on three main devices for developer testing with API 12, phased out Developer Beta cycles. | September 5, 2024 |
| NEXT.0.0.66(SP6C00E66R5P9) - Beta 1 | 5.0.0.66(API 12 release) | September 12 update released a patch version of the NEXT Beta 1 version | September 12, 2024 |
| NEXT.0.0.68 (SP7C00E68R4P9log) - Beta 1 | 5.0.0.68(API 12 release) | September 21 update released a patch version of the NEXT Beta 1 (internal beta) version | September 21, 2024 |
| NEXT.0.0.70 (SP3C00E70R4P14) - Beta 1 | 5.0.0.70 (API 12 Release) | September 27 update released a patch version of the NEXT Beta 1 (internal beta) version with enhancements, fixes ahead of consumer beta October 8 build for existing internal beta users. | September 27, 2024 |
| NEXT.0.0.71(SP6C00E71R1P13) - Beta 1 | 5.0.0.71 (API 12 Release) | October 7 update released a patch version of the NEXT Beta 1 (beta) version with enhancements, fixes ahead of consumer beta October 8 launch for existing internal beta users and joining users via myHuawei app. | October 7, 2024 |
| NEXT.0.0.71(SP6C00E71R1P13) - Beta 1/Release | 5.0.0.71 (API 12 Release) | HarmonyOS NEXT official consumer beta release for expanded models for single frame HarmonyOS 5.0 version with API 12. Starting with existing registered internal beta users of three models, Mate 60, Mate X5 and MatePad Pro 13.2 users. | October 8, 2024 |
| NEXT.0.0.71(SP10C00E71R4P17) - Beta 2/Release | 5.0.0.71 (API 12 Release) | HarmonyOS Next update with exFAT support and charging improvements, alongside other fixes. | October 13, 2024 |
| NEXT.0.0.72 - Release | 5.0.0.71 (API 12 Release) | Patch of changes introduced in the system ROM version updated on October 18th such as security control offset property setting and Media Library Kit improvements. | October 18, 2024 |
| NEXT.0.0.72(SP10C00E72R4P17) | 5.0.0.71 (API 12 Release) | Added features of one click lock screen, service cards and control panel enhancements. | October 20, 2024 |
| 5.0.0.102(SP3C00E73R4P17) | 5.0.0.102 (API 12 Release) | HarmonyOS NEXT 5 public beta rollouts commences. | October 22, 2024 |
| 5.0.0.102(SP3C00E73R4P17) - Release | 5.0.0.102 (API 12 Release) | Release build launch | October 23, 2024 |
| 5.0.0.103 - Release (Beta) | 5.0.0.103 (API 12 Release) | HarmonyOS NEXT 5 branded "public beta" release as HarmonyOS 5.0.0. Move to commercialisation for single-frame builds. Updated developer tools and documentations. | October 23, 2024 |
| 5.0.0.107 SP8 | 5.0 (API 12 Release) | Commercialisation of "HarmonyOS NEXT"; retrofitting on to the Galaxy Edition of the "HarmonyOS 5" name; HarmonyOS 5.0.1 installed on supported Huawei consumer flagship-devices on 26 November 2024; end of beta stage and move to "stable" for Chinese developers with API 12. | November 19, 2024 |