nRF Connect SDK Essential

Software development kit for building IoT products with Bluetooth Low Energy, Wi-Fi, cellular IoT, Bluetooth Mesh, Thread, Zigbee, Matter and more

nRF Connect SDK is a unified and flexible software development kit for building products based on all of Nordic’s nRF54, nRF53, nRF52, nRF70 and nRF91 Series wireless devices. It offers a framework for developing low-power and secure IoT devices that can scale from simple implementations for constrained devices and use cases, to the most feature-rich and sophisticated applications.

It is based on the open source Zephyr project combined with Nordic proprietary software, offered as a single package optimized for Nordic’s portfolio of wireless products. This powerful and comprehensive blend provides developers with a breadth and depth of functionality available out of the box: samples, wireless stacks, networking protocols, drivers, security, and much more. This ensures that developers can focus their time and energy where it matters most, in adding value and differentiation to their application.

The nRF Connect SDK can be extended via Add-ons that provide additional components contributed by both Nordic as well as partners. Add-ons can provide a variety of functionality, from applications, samples, protocols or more complete SDKs for specific technologies and use cases.

In parallel with Zephyr-RTOS based application development, there is the additional nRF Connect SDK Bare Metal option for developing simple Bluetooth LE applications on the nRF54L Series, that do not benefit from an RTOS or advanced features. This offers developers additional flexibility to choose the software development approach that better fits their use case.

The nRF Connect SDK is supported by Nordic’s extensive and industry-leading suite of development tools, including nRF Connect for Desktop, nRF Connect for Mobile, and nRF Connect for VSCode that offers a full-fledged IDE environment to develop your next breakthrough IoT application on Nordic hardware and software.

To onboard developers on nRF Connect SDK as quickly as possible and accelerate their learning curve, Nordic offers online interactive courses through the Nordic Developer Academy, covering a variety of topics and including hands-on exercises.

Documentation
Install and Get started
nRF Connect SDK Fundamentals Course

Zephyr Project

Purpose-built for IoT

As Nordic was looking to expand the technology offering beyond Bluetooth LE, it became clear that the sophistication of our hardware roadmap and the requirements for future IoT applications demanded a strategic move to adopt an RTOS platform to build our next generation SDK. 

After evaluating several alternatives, we found Zephyr RTOS to match the key requirements and qualities that were looking for to create an SDK that would power the next billion IoT devices:

  • Modern: ability to grow alongside our portfolio and be future-proof
  • Scalable: from small to large devices and applications
  • Complete: from low-level drivers to cloud connectivity

 

The year was 2016 and Zephyr was at its infancy, but Nordic saw the potential and how it could help us deliver the best possible software offering to our customers for years to come. We made the strategic decision to build our nRF Connect SDK around the Zephyr Project and Nordic has been the top contributor to the project with roughly a quarter of total contributions.

Nordic and Zephyr

A journey of growth

Zephyr

Explore Zephyr, a secure, modular RTOS built for embedded and IoT devices—used in Nordic Semiconductor’s nRF Connect SDK for connected product development.

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nRF Connect SDK or Upstream Zephyr?

Comparison between nRF Connect SDK and Upstream Zephyr project

The nRF Connect SDK is built around our downstream fork of the upstream Zephyr project, inheriting all the functionality from Zephyr as part of nRF Connect SDK.

While it's possible to develop IoT applications for Nordic wireless SoCs with the upstream Zephyr project, the nRF Connect SDK brings significant value to customers, improving developer experience and accelerating time-to-market. Some of the key differences between nRF Connect SDK and upstream Zephyr are highlighted in the table below.

 
nRF Connect SDK 
Upstream Zephyr Project
Applications
  • Demonstrate typical user scenarios with Nordic devices
  • Each includes a full software stack for product development
  • Built using SDK drivers and libraries for specific use cases
Yes
No
Extensive development tool support, including:
  • nRF Connect for VS Code
  • nRF Connect for Desktop
  • Mobile apps
Yes
No
Wireless technologies such as:
  • Matter
  • Zigbee
  • Amazon Sidewalk
  • Multiprotocol
  • LTE-M / NB-IoT / NTN
  • DECT NR+
  • NFC
Yes
No
Nordic's market-proven Bluetooth LE SoftDevice controller
Yes
No
(Zephyr Bluetooth LE controller)
Vendor neutral
No
Yes
Fully tested by Nordic
Yes
No
Bluetooth qualified
Yes
No
(The customer must qualify)
Nordic Tech support
Yes
No
(Community supported)

Learn more

Nordic webinar

How Zephyr became the leading open-source RTOS for IoT