It has a microkernel design with single framework: the operating system selects suitable kernels from the abstraction layer in the case of devices that use diverse resources.

[17][18][19] "To address security concerns" arising from varying devices, the system provides a hardware-based Trusted Execution Environment (TEE) microkernel to prevent leakage of sensitive personal data when they are stored or processed.

[21][22][23][24] When it launched the operating system, Huawei stated that HarmonyOS plans to become a microkernel-based, distributed OS that was completely different from Android and iOS in terms of target market towards Internet of things.

[26][27][28] At its launch as an operating system for smartphones in 2021, HarmonyOS was, however, rumored by Ars Technica to be a "rebranded version of Android and EMUI" with nearly "identical code bases".

[29] Following the release of the HarmonyOS 2.0 beta, Ars Technica and XDA Developers suggested that "the smartphone version of the OS had been forked from Android 10".

Ars Technica alleged that it resembled the existing EMUI software used on Huawei devices, but with all references to "Android" replaced by "HarmonyOS".

[30][31] These reports intensified during the Sino-American trade war, after the United States Department of Commerce added Huawei to its Entity List in May 2019 under an indictment that it knowingly exported goods, technology and services of U.S. origin to Iran in violation of sanctions.

[32][33][34][35][36] Huawei executive Yu Chengdong [zh] described an in-house platform as a "plan B" in case it is prevented from using Android on future smartphone products due to the sanctions.

[37][38][39] Prior to its unveiling, it was originally speculated to be a mobile operating system that could replace Android on future Huawei devices.

[44] The same day, Huawei registered trademarks surrounding "Ark OS" and variants with the European Union Intellectual Property Office.

[45] In July 2019, it was reported that Huawei had also registered trademarks surrounding the word "Harmony" for desktop and mobile operating system software, indicating either a different name or a component of the OS.

It also integrated the LiteOS SDK for TV applications and ensured compatibility with Android apps through the Ark Compiler and a dual-framework approach.

This setup enabled Android APK files and App Bundles (AAB) to run natively, similar to older Huawei EMUI-based devices, without needing root access.

Huawei also released the DevEco Studio IDE, which is based on IntelliJ IDEA, and a cloud emulator for developers in early access.

[60][61][28] On July 27, 2022, Huawei launched HarmonyOS 3 providing an improved experience across multiple devices such as smartphones, tablets, printers, cars and TVs.

On the same day, the company announced its incoming HarmonyOS 5.0 operating system version of Galaxy Edition version under HarmonyOS NEXT system that will first be released as open beta program for developers and users at its annual Huawei Developer Conference in June 2024 before Q4 commercial consumer release with upcoming Mate 70 flagship, among other ecosystem devices.

[93][94] They are developed based on the industry standards formulated by the Quick App Alliance, comprising mainstream mobile phone manufacturers in China.

[99][98][100] They can also be synchronized across multiple devices, such as updating the driver's location on the watch in real time after the user hails a taxi on the mobile phone.

The Service Collaboration Kit (SCK) provides users with cross-device interaction, allowing them to use the camera, scanning, and gallery functions of other devices.

These features improve performance, reduce power consumption, and enable efficient AI processing on devices with Kirin chips.

[112][113][114] Incorporated into HarmonyOS 4, NearLink (previously known as SparkLink) is a set of standards that combine the strengths of traditional wireless technologies like Bluetooth and Wi-Fi, while emphasizing improved performance in areas like response time, energy efficiency, signal range, and security.

Huawei opened up APIs to help automobile OEMs, suppliers and ecosystem partners in developing features to meet user requirements.

[135] On December 21, 2021, Huawei launched a new smart console brand, HarmonySpace, a specialized HarmonyOS vehicle operating system.

[136][137] On December 23, 2021, Huawei announced a new smart select car product – AITO M5, a medium-size SUV with HarmonyOS ecosystem through continuous AI learning optimization and over-the-air upgrades.

[139] Huawei MagLink built on interconnected Cockpit solution, enables drivers to make the mobile phone application full amount of car, no need for telephony navigation.

The research claimed that in the first quarter of 2022 the platform outgrew its rivals, such as Android and Apple iOS, from a low install base of about 150 million smart devices overall, particularly due to the good support in China and the HarmonyOS software upgrades that Huawei made available for its older handset models and its former sub-brands such as Honor.

[147][148] In the third quarter of 2023, HarmonyOS captured a 3% share of the global smartphone market and 13% within China, despite Huawei's limitation to LTE at the time.

[155] In terms of architecture, HarmonyOS has close relationship with 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.

[158] The open-source operating system contains the basic capabilities of HarmonyOS and does not depend on the Android Open Source Project (AOSP) code.

[163] In less than a week before launching HarmonyOS 2.0 and new devices by Huawei, the Beijing Intellectual Property Court announced the first-instance judgement in May 2021 to uphold the decision by CNIPA as the trademark was not sufficiently distinctive in terms of its designated services.