OpenHarmony (OHOS, OH) is a family of open-source distributed operating systems based on HarmonyOS derived from LiteOS, donated the L0-L2 branch source code by Huawei to the OpenAtom Foundation.

[8] The first version of OpenHarmony was launched by the OpenAtom Foundation on September 10, 2020, after receiving a donation of the open-source code from Huawei.

[13] Hardware development is developed using DevEco Studio via DevEco Device tool for building on OpenHarmony, also creating distros with operating system development with toolchains provided, including verification certification processes for the platform, as well as customising the operating system as an open source variant compared to original closed distro variant HarmonyOS that primarily focus on HarmonyOS Connect partners with Huawei.

[16][17] Like HarmonyOS, OpenHarmony uses App Pack files suffixed with .app, also known as APP files on AppGallery and third party distribution application stores on OpenHarmony-based and non-OpenHarmony operating systems such as Linux-based Unity Operating System which is beneficial for interoperability and compatibility.

[19] Unlike with open-source Android operating system with countless third-party dependency packages repeatedly built into the apps at a disadvantage when it comes to fragmentation.

The file system suitable for scenarios where large-scale data storage and processing are essential, such as IoT applications, edge computing, and cloud services.

[26][27] OpenHarmony can be deployed on various hardware devices of ARM, RISC-V and x86 architectures with memory volumes ranging from as small as 128 KB up to more than 1 MB.

Public Basic Class Library supports Thread Pools, "workers" within HSP and HAR modules of HAP apps.

As of September 2023, it has over 30 open-source software distributions compatible with OpenHarmony for various sectors such as education, finance, smart home, transportation, digital government and other industries.

[53][54][55][56] On January 6, 2022, OpenHarmony in Space (OHIS) by OHIS Working Group and Dalian University of Technology led by Yu Xiaozhou was reported to be a vital play in the future from a scientific and engineering point of view, expecting to open up opportunities for development in China's satellite systems, and surpass SpaceX’s Star Chain plan with the idea of micro-nano satellite technology.

[57] Based on OpenHarmony, SwanLinkOS was released in June 2022 by Honghu Wanlian (Jiangsu) Technology Development, a subsidiary of iSoftStone, for the transportation industry.

The operating system supports mainstream chipsets, such as Rockchip RK3399 and RK3568, and can be applied in transportation and shipping equipment for monitoring road conditions, big data analysis, maritime search and rescue.

[citation needed] An intelligent terminal operating system for enterprises in China by Tongxin Software was passed for compatibility certification on June 7, 2023.

Tongxin has established cooperative relations with major domestic mobile chip manufacturers and has completed adaptations using the Linux kernel.

[68] LightBeeOS launched on September 28, 2023, is an OpenHarmony-based distro that supports financial level security, with distribution bus by Shenzhen Zhengtong Company used for industrial public banking solutions of systems, tested on ATM machines with UnionPay in Chinese domestic market.

[74] The goal is to increase the distro with partners that create their own OpenHarmony-Oniro compatible distros that increase interoperability which reduces fragmentation of diverse platforms with diverse set of hardwares with enhancements from derived project back to original project in Upstream development of OpenHarmony source code branch to improve global industrial standards compatibilities customised for global markets.

It is also used for Downstream development for enhancing OpenHarmony base in global and western markets for compatibility and interoperability with connected IoT systems as well as custom third-party support on-device AI features on custom frameworks such as Tensorflow, CUDA and others, alongside native Huawei MindSpore solutions across the entire OpenHarmony ecosystem.

[75][76] Rust in a framework alongside the Data Plane Development Kit (DPDK) IP Pipeline and profiling, React Native and Kanto in Applications development system on top of OpenHarmony, Servo and Linaro tools in system services, Matter opеn-sourcе, royalty-frее connеctivity standard that aims to unify smart homе dеvicеs and incrеasе thеir compatibility with various platforms and OSGi in driver subsystem, IoTex in swappable kernel development, and Eclipse Theia in integrated development environment to build Oniro OS apps that has interoperability with OpenHarmony based operating systems.

Data can be transmitted directly rather than being shared via cloud online, enabling low latency architectures in more secure methods and privacy functions suitable for AIoT and smart home devices integration.

[77][78] In September 2023, Open Mobile Hub (OMH) led by Linux Foundation was formed, as an open-source platform ecosystem that aims to simplify and enhance the development of mobile applications for various platforms, including iOS, Android, and OpenHarmony based global Oniro OS alongside, HarmonyOS (NEXT) with greater cross platform and open interoperability in mobile with OMH plugins such as Google APIs, Google Drive, OpenStreetMap alongside Bing Maps, Mapbox, Microsoft, Facebook, Dropbox, LinkedIn, X and more.

[85] In the long term, as the company builds up the software root in downstream development for both domestic Chinese and global markets, the closed HarmonyOS NEXT customised L0-L2 full branch source code of the OpenHarmony operating system is aimed to replace the current closed-source L3-L5 branch since OpenHarmony 2.2 fork branch with 8GB worth of code up to 4.x with 60% codebase designed with a dual-frame architecture that is compatible with Android with EMUI userland in the multi-kernel architecture of HarmonyOS from current Linux kernel on phones and tablets, cars, TVs and advanced wearables, alongside lightweight LiteOS kernel on basic wearables and various IoT smart devices.

[91][92] In terms of architecture, OpenHarmony alongside HarmonyOS has close relationship with server-based multi-kernel operating system OpenEuler, which is a community edition of EulerOS, as they have implemented the sharing of kernel technology as revealed by Deng Taihua, President of Huawei's Computing Product Line.