Top 10 IoT Boards for Development & Prototyping in 2021


Facebook Twitter Link

What’s the most exciting thing happening right now in internet of things (IoT) hardware? At a high-level, it’s the fact that we’re now able to achieve Agile hardware development through a rapid prototyping process and early integration with the rest of the IoT device tech stack. Picking the right microcontroller is crucial for this process. To guide that search, we favor microcontrollers that have (hopefully open source) development kits (dev kits) available.

If you had told me even a year or two ago that embedded Linux would be a better option for many applications over embedded C, I would have told you that you were out of your mind. However, the physical size and cost of Linux capable microcontrollers decreased so much that moving from bare metal programming or real-time operating systems (RTOS) to a full-blown OS has never looked so attractive.

Our preferred Linux solution is Nerves, an IoT-specific platform written in Elixir that lets us build custom Linux systems. 2021 is going to bring Nerves into a space that it’s never been before, which in turn will foster even greater agility.

Embedded Linux simplifies integration. We can now create a minimum viable product (MVP) in less than six months for many projects, while the same thing would have easily taken over a year before.

What Is a Dev Kit? 

A dev kit is basically a tiny, hackable computer that’s made for tinkering. Generally, they provide easy access to input/output (I/O) pins so that we can build custom circuitry and start developing the firmware to run the components. Dev kits give us a base to build on.

What Should I Look for in an IoT Board?


When picking an IoT board, one of the first things that I always look for is the connectivity options—after all, smart devices are largely defined by their connectivity. 

Does our development board include built-in Wi-Fi? How about Bluetooth? Ethernet? Depending on our project’s requirements, we’ll select a kit that has what we need and nothing more.

Another main factor is support for peripherals and features that we want. 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. Again, this comes down to knowing most of the product specifications before we start building.

Lastly, open source hardware (OSHW) is always a big plus. KiCAD design files are preferred to any other CAD format. However, I’m always happy if the schematic and  Gerber files (files that show the printed circuit board (PCB) designs) are provided. 

Sign up for our newsletter

Join 10,000+ subscribers to get the latest IoT development news delivered to your inbox.

What Are the Top 10 IoT Boards in 2021?


Now, without further ado, here are my top 10 IoT boards for product development and rapid prototyping in 2021. As of the writing of this blog, all of the boards listed come in under the $100 mark, making them a solid choice for rapid prototyping on your next IoT project.  

1) Giant Board

Coming in at the top of the list is a board that I can’t wait to get my hands on. The Giant Board is the first-ever single-board computer (SBC) to come in the Adafruit Feather form factor, and this a serious piece of OSHW that’s made to take advantage of Adafruit's Blinka libraries for CircuitPython. The Giant Board also comes preloaded with Debian Linux, and reflashing it with Nerves is going to push our favorite embedded Linux platform into a whole new arena.

Technical specs:

  • Processor: Microchip SAMA5D2 ARM® Cortex®-A5 Processor @ 500 MHz
  • Memory: 128 MB DDR2 RAM
  • Storage: MicroSD
  • Sensing: I2C, SPI, UART, 6 12-bit ADC with 3.3V reference and external trigger
  • Actuation: Four 16-bit PWM with external triggers
  • Connectivity: Not included
  • Power: USB, with support for LiPo batteries

2) Discovery STMP32MP157C Crypto Board

The main draw of this board from ST is their STM32MP157 microprocessor. Just like the Giant Board, this kit supports embedded Linux development. One of the main differentiators is the dedicated 3D graphics processing unit (GPU) that powers the HDMI attached LCD display with 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 in TFBGA361 package
  • Memory: 4Gbit DDR3L @ 533 MHz
  • Storage: MicroSD
  • Sensing: Touch screen, stereo headset jack with analog microphone, two GPIO expansion connectors for Arduino and Raspberry Pi Shields
  • Actuation: Four user LEDs, LCD display
  • Connectivity: Ethernet, Wi-Fi, Bluetooth
  • Power: 5V/ 3A USB Type-C power supply

3) OSD32MP1-BRK Flexible Prototyping Platform

Coming in third is a breakout board from Octavo Systems that’s built around their OSD32MP15x System-in-Package (SiP). This unique integrated circuit (IC) includes a STM321MP microprocessor, just like our previous board, but it goes one step further by integrating the RAM, power management IC, EEPROM storage, and other features into one tidy package. We’d use this board if we want to do rapid prototyping for a custom PCB that will revolve around the Octavo SiP.

Technical Specs:

  • Processor: ST32MP15x ARM® dual Cortex®-A7 @ 800MHz + Cortext®-M4 @ 209MHz
  • Memory: 512 MB DDR
  • Storage: MicroSD, 4KB non-volatile EEPROM
  • Sensing: 106 GPIO, UART
  • Actuation: 106 GPIO, four user LEDs
  • Connectivity: SiP supports multiple channels, but not built into dev kit
  • Power: MicroUSB

4) BeagleBone® Green Gateway

Developed by Seeed Studio in conjunction with, this OSHW shines for custom IoT gateway development because it comes pre-equipped with all of the necessary connectivity features: Ethernet, Wi-Fi, and Bluetooth Low Energy (BLE).

Other unique features include 2 32-bit programmable real-time units (PRUs) @ 200MHz. Combined with the real-time functionality of Nerves, this makes this dev kit perfect for industrial internet of things (IIoT) applications that require extremely low latency for deterministic control. There are also ports for Seeed’s unique Grove sensors, which speeds up integration along with the standard BeagleBoard headers.

As this is a high-end board, its major drawback is that it’s more expensive than others on this list.

Technical Specs:

  • Processor: AM3358 ARM® Cortext®-A8 @ 1 GHz with 2 32-bit PRUs @ 200 MHz
  • Memory: 512MB DDR3
  • Storage: 4GB eMMC, 4KB EEPROM
  • Sensing: 92 GPIO, I2C, UART
  • Actuation: 92 GPIO
  • Connectivity: Ethernet, Wi-Fi, Bluetooth
  • Power: MicroUSB and 12V DC

5) ESP32-SE2-Saola-1

On the other end of the spectrum, we have a board that’s based on Espressif’s low-end ESP32 chip. While the documentation isn’t great and we certainly can’t boot Linux on here, these chips are affordable, suitable for many consumer IoT devices, and come with Wi-Fi.

Technical Specs:

  • Processors: ESP32-S2-WROVER with Xtensa® 32-bit LX7 @ 240 MHz
  • Memory: 2MB PSRAM, 320KB SRAM, 16KB SRAM in RTC
  • Storage: 128KB ROM, 4MB external SPI flash
  • Sensing: 46 GPIO, I2C, SPI, UART, USB-UART bridge
  • Actuation: 46 GPIO, PWM, addressable RGB LED
  • Connectivity: Wi-Fi
  • Power: MicroUSB

6) SimpleLink Wi-Fi CC3200 LaunchPad

A stand-in for Texas Instruments’s entire range of SimpleLink products, these dev kits can include support for any number of IoT communication protocols beyond the standard ones that we’ve seen above. These include more mature protocols like Zigbee and relative newcomers like Thread. Other niceties include on-board accelerometers and temperature sensors.

Technical Specs:

  • Processor: CC3200 SimpleLink Wi-Fi with ARM® Cortex®-M4 Core @ 80 MHz
  • Memory: Up to 256KB SRAM
  • Storage: 64KB ROM
  • Sensing: 40 GPIO, I2C, SPI, UART
  • Actuation: 40 GPIO, 3 LEDs
  • Connectivity: Varies
  • Power: MicroUSB or 2 AA batteries with BoosterPack

7) BeagleBone Black

Another BeagleBoard product, the Black was one of Nerves’ first targets because it has so many features that are attractive for IoT development. Besides its open source status, we like to use the Black and Black Wireless because they offer great performance. Everything that was said about the BeagleBone Green holds here minus Ethernet + Wi-Fi/BT on a single board. 

Technical Specs:

  • Processor: AM335x ARM® Cortex®-A8 @ 1 GHz with 2 32-bit PRUs @ 200 MHz
  • Memory: 512MB DDR3
  • Storage: 4GB eMMC
  • Sensing: 92 GPIO, I2C, SPI, UART
  • Actuation: 92 GPIO, 4 user LEDs
  • Connectivity: Ethernet, optional Wi-Fi
  • Power: MicroUSB, 5V DC

8) 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. One great use case is putting an RPi out in a box in the field while developing the product on another dev kit. Just letting it run can gather a lot of valuable info.

There are also quite a few options to choose from, including the RPi 4 with 2GB, 4GB, or even 8GB of memory; the compute module 3+, which is easily designed as a system-on-module (SOM); and the RPi 0 W, which is even cheaper and suited for less intensive applications.

Technical Specs (RPi4 B+):

  • Processor: Broadcom BCM2711, Quad core ARM® Cortex®-A72 64-bit @ 1.5 GHz
  • Memory: 2GB, 4GB, or 8GB LPDDR-3200 SDRAM
  • Storage: microSD
  • Sensing: 40 GPIO, I2C, SPI, UART, MIPI CSI camera port
  • Actuation: 40 GPIO, PWM, MIPI DSI connector
  • Connectivity: Ethernet, Wi-Fi, Bluetooth
  • Power: 5V USB-C, Power over Ethernet (PoE) 

9) Particle Boron LTE CAT-M1

This feather form factor dev kit bears more resemblance to the ESP32 than any other board on our list, but there’s one major difference — cellular connectivity, and the fact that it’s open source. For IoT devices in remote locations, LTE is a must, and so this board by Particle simplifies the bring-up for these devices. It also provides a very quick path to early prototyping and field testing.

Technical Specs:

  • Processor: Nordic Semiconductor nRF52840 SoC ARM® Cortex®-M4F 32-bit @ 64 MHz
  • Memory: 256KB RAM
  • Storage: 1 MB ROM, 4MB on-board SPI flash
  • Sensing: 20 mixed signal GPIO, including I2C, SPI, UART, and 6 ADCs
  • Actuation: 20 mixed signal GPIO, including 8 PWM, and user RGB LED
  • Connectivity: Cellular LTE, Bluetooth
  • Power: microUSB, integrated Li-Po charging and battery connector

10) SeeedStudio NPi i.MX6ULL Dev Board 

The last board on our list also brings something unique to the table: the i.MX6 Applications Processor, a unique chip that’s tailored towards multimedia devices that utilize sound, video, voice, pictures, and touch. This processor can handle up to HD 1080p encode and decode, 3D video playback in high definition, and HD 1080p videoconferencing, giving it a unique position in the MCU marketplace.

The dev board in particular boasts 2x 100Mb Ethernet ports, 24-bit RGB display interface, a Raspberry Pi expansion header, and a secondary 40 position GPIO header. 

Technical Specs:

  • Processor: i.MX 6Qiuad @ 800MHz, based on ARM® Cortex®-A7 core
  • Memory: 512MB DDR3L RAM
  • Storage: 8GB eMMC
  • Sensing: I2C, SSI, SPI, Touch screen interface
  • Actuation: 2x 40 GPIO (one RPi compatible), 
  • Connectivity: 2x Ethernet
  • Power: USB, 5V barrel jack


Development kits are at the heart of any agile IoT project, and that’s why it’s so important to weigh all the options and choose the right one for the job. By making the right decision, we can cut costs, reduce time to market, and build in all the features that we want.

If you want to learn more about how Very approaches IoT development, drop us a line here.