The Internet of Things (IoT) is rapidly changing the types of connectivity and communications that happen between devices, which is leading to an urgent need for operating system technologies that can tackle the challenges inherent to IoT environments. Lightweight operating systems for IoT have been specifically designed for devices that have constraints in processing power, memory, and energy usage. The characteristics of these systems, aside from efficiency, allow IoT devices to perform tasks that require real-time response, maintain connectivity, and stabilize security in place. As IoT devices are becoming prevalent in markets around the world, including in the smart home, wearable, and industrial sensor markets, the necessity for efficient, flexible, and secure IoT operating systems will continue to rise to support developers in creating reliable and scalable offerings to the connected world.

1. Zephyr

Zephyr is an open-source IoT operating system (OS) for constrained resource devices. It is lightweight with little memory and supports multiple hardware architectures. Along with hardware-level connectivity options like Wi-Fi, Bluetooth, and Ethernet, it offers modularity features to include strong security components, such as authentication and encryption. Power management techniques are also implemented for longer device lifecycle to allow the OS to be used in sensors, wearables, and gateways.

2. FreeRTOS

FreeRTOS is a real-time operating system from Amazon, for microcontrollers with limited memory. FreeRTOS is popular in IoT because it has a small footprint (6-15 KB) and enables robust programming for edge devices. It integrates easily with AWS IoT services like IoT Core and Device Defender while providing both cloud connectivity and security. Among its features – over-the-air updates facilitate remote management of IoT devices.

3. Contiki (Contiki-NG)

Contiki is an operating system developed for the purpose of connecting tiny, low-power microcontrollers with the Internet. It supports IPv6 – the Internet’s next generation protocol, low-power wireless protocols – 6LoWPAN and RPL, as well as multi-threaded multitasking. Contiki also runs on severely constrained hardware resources (about 10 KB RAM), and it has been widely used for sensor networks and wireless embedded systems. Contiki’s simulation environment – Cooja allows developers to simulate their IoT application for testing before deploying the application.

5. Ubuntu Core

Ubuntu Core is a stripped-down, containerized edition of Ubuntu Linux designed for IoT and embedded devices. It has security as a top priority as it uses immutable packages and digitally signed packages, making it suitable for mission-critical IoT deployments. The OS runs on cloud platforms and hosts networking technology while providing a trusted operating environment for IoT gateways, robots, and industrial devices. Canonical provides official training and community support for developers.

Conclusion

The growing IoT ecosystem demands lightweight, efficient, and secure operating systems to power billions of connected devices. Zephyr, FreeRTOS, Contiki, TinyOS, and Ubuntu Core stand out as top choices, offering diverse features tailored to the needs of constrained devices while supporting modern connectivity and security standards. Investing in skill development courses focused on these operating systems empowers developers to build robust IoT solutions that are scalable and secure. As IoT adoption accelerates, mastering these platforms will be critical for innovating across smart homes, industrial automation, healthcare, and beyond.

These operating systems’ continual evolution and supportive communities ensure they remain instrumental in addressing the challenges of IoT application development and deployment in 2025 and beyond. Exploring learning paths and participating in IoT OS training can unlock significant career opportunities in the rapidly advancing IoT technology landscape.