Top IoT Boards for Development & Prototyping: 2023 Update

Leveraging the Agile methodology for IoT hardware development, however, begins with using the right kind of board. In this article, we’ll explore our top picks for microcontrollers, microprocessors, and IoT boards necessary for building a robust IoT product.  

Dev Kits, Defined 

You’ll hear us reference “dev kits” frequently throughout this article. In short, a dev kit is a tiny, hackable computer that’s made for tinkering. 

More specifically, dev kits are usually single board computers (SBCs) that include pre-certified RF communications natively on the board. Generally, they provide easy access to input/output (I/O) pins so that we can interface with custom circuitry and start developing the firmware to run the components. Dev kits provide us with a base for building IoT devices and include IoT boards.

Think of a dev kit as a premade meal you purchase at a store and heat up quickly in your home oven. If you like it, you might later create a similar meal from scratch that’s customized to suit your unique preferences. We use dev kits to determine if we like the “taste” of the ingredients, then we assemble a custom “meal” from the ingredients to suit our client’s needs.

Choosing a Microcontroller (MCU) or Microprocessor (MPU)

Your choice of processor — MCU or MPU — will impact your bill-of-materials cost. A lower-powered MCU that runs either on embedded C or a real-time operating system (RTOS) will cost less than the more powerful MPU, which can run embedded Linux. 

However, while cost is one dimension of MCU vs MPU selection, a much more important one is capability. It comes down to software/firmware complexity. If all you need to do is read some sensors and transmit the data, an MCU is probably the best choice because it’s cheap and low power. If you need to do more complex operations such as machine learning or edge-hosted applications, then you’ll want a more powerful MPU — which will cost more and use more power.

MPU + Linux

At Very, our preferred Linux solution is Nerves, an IoT-specific platform written in Elixir that lets us build custom Linux systems. Nerves enables us to have a baseline target system up and running in a matter of weeks, and we can create a minimum viable product (MVP) in less than six months for many projects.

MCU + Embedded C/RTOS

We’ve been successful in our recent work with Zephyr RTOS, an embedded C framework that provides for built-in support for over 350 boards. It’s easily set up, scalable, and isn’t tied to any particular cloud offering. Most importantly, Zephyr makes it surprisingly easy to recompile the firmware for a different processor family by changing only one line of code. This allows us to bring the portability of embedded Linux to the lower-level, lower-cost world of microcontrollers.

Choosing an IoT Board: What To Look Out For

As you begin your search for an IoT board, look out for four critical components.

The first is the board’s connectivity options. This goes without saying, given that a smart device is largely defined by its connectivity capabilities. 

You’ll also want to make sure the board supports peripherals and desired features. These can include common ports like USB or HDMI, buses for serial protocols like I2C and SPI, or pin-outs for pulse width modulation (PWM) devices like dimmable lights or servo motors. 

Lastly, open source hardware (OSHW) is always a big plus. It’s a good sign if schematic and Gerber files — files that show the printed circuit board (PCB) designs —  are provided, too. 

Top IoT Boards and Dev Kits in 2023

Without further ado, here are our top nine IoT boards for product development and rapid prototyping in 2023. As of the writing of this blog, all of the boards listed come in under the $100 mark.  

1) i.MX6ULL Colibri SOM + Colibri Evaluation Kit

A new favorite target of ours is the NXP i.MX6ULL. It offers many of the same connectivity options as our older favorite MPUs, but there seems to be more of the i.MX6ULL family in stock. Unfortunately, that has not held true for some of the dev kits we liked in the past that hosted this target. When we went searching for a new dev kit to keep developing with the i.MX6ULL, we found the Toradex Colibri i.MX6ULL SOM. This can be paired with one of many host boards, but we have been working with the full-featured Colibri Evaluation Board. There are several other options available for carrier boards though.

What is great about the SOM is that, if the project has enough space and budget, it is possible to just place a SODIMM connector on a host board, and this frees up time to focus on designing the peripherals and larger product. This is helpful for two reasons. First, everything needed for the MPU to run is hosted on the SOM – just provide main input power. Second, Toradex provides the design files for their carrier boards. If they are used as a reference, then it is possible to go back to a known working design should you find yourself debugging your custom design.

Technical Specs:

• Processor: NXP i.MX 6ULL @ 800MHz, based on ARM® Cortex®-A7 core
• Memory:
  • 4GB eMMC for long-term storage, MicroSD
  • 1GB DDR3L RAM for computing power
• Low Level IO: SDIO, I2C, SPI, UART, PWM, GPIOs, CAN, USB
• Multimedia: Display – LVDS, HDMI, VGA, RGB; Audio – analog line in, analog mic in, analog headphone out
• Inputs: Resistive touch, Capacitive touch, Buttons, MIPI CSI camera port
• Connectivity: 10/100 Mb Ethernet, USB OTG
• Power: 7 – 27V DC into terminal block, barrel jack, header

2) nRF52840 DK

The nRF52840, developed by Nordic Semiconductors, is really a stand-in for the entire nRF52 series. It’s a system-on-chip (SoC) that provides a robust development platform for BLE5.3 devices. It’s well supported by Zephyr RTOS and has an excellent low-power sleep mode, making it a  great target for battery-powered devices. It can run on either a 1.8V or 3.3V power rail, and the nRF52840 DK includes a native coin cell battery. There are several perks associated with the  nRF52 series SoCs, but this dev kit in particular has a built-in JLink that can program and debug external nRF52 targets.

Technical Specs:

• Processor: Nordic Semiconductors nRF52840
• Memory:
  • 1MB internal flash
  • 256kB internal RAM
• Low Level IO: I2C, SPI, UART, PWM, GPIOs, I2S, USB, ADC
• Multimedia: Audio – I2S
• Inputs: Buttons
• Connectivity: BLE5.3, NFC, USB OTG
• Power: USB connectors, headers, coin cell

3) Discovery Kit with STMP32MP157A MPU

This board’s main draw is its  STM32MP157 microprocessor, which also supports embedded Linux development. One of its key differentiators is its dedicated 3D graphics processing unit (GPU) that powers the MIPI attached LCD display with a touch panel. There’s even an audio codec for good measure.

The internal M4 MPU enables hard real-time and lower power mode. This board also offers Ethernet, Wi-Fi, and Bluetooth connectivity. Altogether, these features make this dev kit great for IoT devices that run user-facing applications.

Technical Specs:

• Processor: STM32MP157 ARM® dual Cortex®-A7 32-bit @ 800 MHz + Cortex®-M4 32-bit MPU @ 209 MHz
• Memory:
  • MicroSD
  • 4Gbit DDR3L @ 533 MHz
• Low Level IO: SDIO, I2C, SPI, UART, 12-bit ADC, PWM
• Multimedia: Display – MIPI DSI 4″ touch screen TFT 480×800 pixels; Audio – Codec
• Inputs: Buttons, Touch screen
• Connectivity: 1Gbps Ethernet, Wi-Fi, BLE 4.2, USB
• Power: 5V/ 3A USB Type-C power supply

4) BeagleBone® Green Gateway

Developed by Seeed Studio in conjunction with BeagleBoard.org, this OSHW shines for custom IoT gateway development. It’s pre-equipped with all of the necessary connectivity features — Ethernet, Wi-Fi, and Bluetooth Low Energy (BLE) — and includes two 32-bit programmable real-time units (PRUs) @ 200MHz.

Combined with the real-time Nerves functionality, this dev kit is perfect for industrial internet of things (IIoT) applications that require extremely low latency for deterministic control. 

It also has ports for Seeed’s unique Grove sensors, which speeds up integration along with the standard BeagleBoard headers.

Technical Specs:

• Processor: AM3358 ARM® Cortext®-A8 @ 1 GHz with 2 32-bit PRUs @ 200 MHz
• Memory:
  • 4GB eMMC, 4KB EEPROM, MicroSD
  • 4Gbit DDR3L @ 533 MHz
• Low Level IO: SDIO, I2C, SPI, UART, 12-bit ADC, PWM
• Multimedia: Display – HDMI, LCD; Audio – Codec
• Inputs: Buttons, Touch screen
• Connectivity: 10/100 Mbps Ethernet, Wi-Fi, BLE 4.2, USB
• Power: 12V DC – Barrel Jack
• BeagleBone Expansion Headers
• Grove connectors 

5) ESP32-S3-DevKitC-1

Another low-cost target is based on Espressif’s ESP32-S3-WROOM modules. They offer price points that are often hard to compete with, and the modules support both Wi-Fi and BLE. The documentation has improved as time goes on, and there’s quite a bit of support for ESP32s in Zephyr RTOS. It comes with either a built-in antenna or a u.FL connector for an external one.

Technical Specs:

• Processor: ESP32-S3-WROOM with Xtensa® 32-bit LX7 @ 240 MHz
• Memory:
  • 128KB ROM, 4MB external SPI flash
  • 2MB PSRAM, 320KB SRAM, 16KB SRAM in RTC
• Low Level IO: I2C, SPI, UART, ADC (not recommended to use), PWM
• Multimedia: Audio – I2S
• Inputs: Buttons
• Connectivity: Wi-Fi, BLE5, USB OTG, USB-UART bridge
• Power: MicroUSB, headers

6) BeagleBone Black

The Black boasts a handful of attractive features for IoT development. Besides its open source status, we like to use the Black and Black Wireless simply because they perform well. Everything that was said about the BeagleBone Green holds true here — minus Ethernet + Wi-Fi/BT on a single board. 

Technical Specs:

• Processor: AM3358 ARM® Cortext®-A8 @ 1 GHz with 2 32-bit PRUs @ 200 MHz
• Memory:
  • 4GB eMMC, 4KB EEPROM, MicroSD
  • 4Gbit DDR3L @ 533 MHz
• Low Level IO: SDIO, I2C, SPI, UART, 12-bit ADC, PWM
• Multimedia: Display – HDMI, LCD; Audio – Codec
• Inputs: Buttons, Touch screen
• Connectivity: 10/100 Mbps Ethernet, Wi-Fi, BLE 4.2, USB
• Power: 5V DC – MicroUSB, Barrel Jack

7) Raspberry Pi 4 Model B

While the popular Raspberry Pi (RPi) only provides limited schematics and design files, this SBC’s low price, common form factor, and general hackability earns it a place on our list. Letting an RPi run in the field — while developing the product on another dev kit — can generate swaths of insightful project data.

Raspberry Pi offers several options to choose from, including the RPi 4 with 2GB, 4GB, or 8GB of memory; the compute module 3+, which is easily designed as a system-on-module (SOM); and the RPi 0 2 W, which is less expensive and suited for less intensive applications.

Technical Specs (RPi4 B+):

• Processor: Broadcom BCM2711, Quad core ARM® Cortex®-A72 64-bit @ 1.5 GHz
• Memory:
  • MicroSD
  • 2GB, 4GB, or 8GB LPDDR-3200 SDRAM
• Low Level IO: I2C, SPI, UART, 12-bit ADC, PWM
• Multimedia: Display – 2x Micro HDMI, LCD; Audio – Codec
• Inputs: Buttons, Touch screen, MIPI CSI camera port
• Connectivity: 1 Gbps Ethernet, Wi-Fi, Bluetooth, USB 2.0 & 3.0
• Power: 5V USB-C, Power over Ethernet (PoE)

8) Feather nRF52840 Express

This dev kit combines Adafruit’s Featherwing footprint with the versatility of Nordic Semiconductors’ nRF52840. The nRF52840-DK is somewhat bulky, but the Featherwing form factor is smaller and provides a wide range of “Feathers” for testing as direct plugins. This provides both OSHW and FW references that can help you kickstart your project.

If you’re looking to put together an early works-like prototype, you can always 3D print a case and solder the Featherwing to a sensor dev kit. 

Technical specs:

• Processor: Nordic Semiconductors nRF52840
• Memory:
  • 1MB internal flash
  • 256kB internal RAM
• Low Level IO: I2C, SPI, UART, PWM, GPIOs, I2S, USB, ADC
• Multimedia: Audio – I2S
• Inputs: Buttons
• Connectivity: BLE5.3, USB OTG
• Power: USB connector, headers, Li-Po battery + charger

9) EVB 2.0 Module Evaluation and IoT Device Development Kit

In certain cases, you won’t always be interested in a target MCU or MPU. Instead, you’ll need to evaluate a new Wi-Fi or cellular module. The Telit EVB 2.0 allows just that, providing a prototyping platform that facilitates connections with several of their target radios. 

For example, the ME910 NB-IoT/Cat-M1 cellular module with GNSS support can be connected directly to a BeagleBone host port. Within a few hours, you’ll be up and running with cellular connectivity.

In many situations the MCU/MPU target dev kit may not have Wi-Fi/BLE on board, and you might want to evaluate the WE866C6 dual-band Wi-Fi module. One option includes using the EVB2.0 to host the WE866C6-P Wi-Fi EVK, which has an SD card form factor for the SDIO interface, and then connecting via USB and a combination of jumpers. Not only are their current modules supported, but Telit aims to build future dev kits that can interface with the EVB 2.0. Having a familiar platform to prototype with can make a world of difference in speeding up your next design.

Choosing The Best Option

The right IoT dev kit is the heart of any Agile IoT project. By choosing the option best suited for your project, you’re able to cut costs, reduce time to market, and build in more of the features you’ve been looking to incorporate.

KEEP READING: Find out how Very helped Tattlebox improve its product-market fit with rapid IoT prototyping.