ESP32 boards are everywhere, even inside smart displays, speakers, and other devices. Many ESP32-based devices can perform multiple functions; each of these devices excels particularly at one task. And they cost far less than their commercial equivalents. That said, these ESP32 devices aren't all plug-and-play.

As long as you’re willing to tinker, ESP32 devices can also offer better control and improved privacy by letting you flash your own firmware and keep all data local. Here are some affordable ESP32-based devices that do one thing perfectly and still exceed expectations.

ReSpeaker Lite

A DIY smart speaker and offline voice assistant

The ReSpeaker Lite ($32) is a ESP32-based audio kit with a 2-mic array from Seeed Studio that can transform your old speakers into smart ones. For that, flash the port of Home Assistant Voice Preview Edition’s firmware to pair it with ESPHome to unlock wakeword support and hands-free control.

Want something more capable than that? Add the ReSpeaker XVF3800 4-microphone array ($60) for better voice pickup and responsiveness like a true Amazon Echo killer, so that you don’t need to repeat your voice commands. It requires a fair amount of tinkering, but ReSpeaker Lite is the most affordable way to build a DIY smart speaker that replaces the big-brand assistants.

M5Stack Atom Echo

A voice satellite and Bluetooth proxy in one

The M5Stack Atom Echo ($14) is a compact ESP32 device featuring a built-in microphone and speaker, designed to act as a satellite node for your DIY voice assistant setup. It can handle the wake-word detection locally on the device, or you can use the Home Assistant Voice pipeline to pass the microWakeWord requests to work as your own private voice assistant.

While you use it as a voice satellite, Atom Echo can also act as a Bluetooth proxy to relay local Bluetooth Low Energy devices to Home Assistant. This tiny cube can then handle those BLE devices and voice control like a capable middleman.

ESP32 Cheap Yellow Display

A makeshift smart home board or weather station

At around $20, the ESP32 Cheap Yellow Display (CYD) is a fun, entry-level “everything screen” featuring an ESP32 inside. Its compact form makes it suitable as a Now Playing, Home Assistant dashboard, or even microSD-card-based music player. If you like tinkering and tweaking, you can turn it into a pocketable weather station. Feeling adventurous? Flash the ESP32 Marauder firmware to turn it into a lightweight network analysis and Wi-Fi penetration-testing device that you can use on the go.

WT32-SC01 Plus

A budget touchscreen control panel PC or NAS

Instead of splurging on a premium HYTE PC case with a touch screen, this WT32-SC01 Plus ($26) gives you that experience for much less. It is ideal for PC dashboards, home servers, or NAS monitoring. With the touch support, you can equip controls for the machines or even the apps running on them.

For example, you can extend OBS controls or add system functions for fast, tactile shortcuts. Besides displaying information, you can bind commands to let it control the PC, home server, or NAS. But mostly, it’s an ideal distraction-free dashboard that provides quick access without requiring you to switch to any apps or open your computer.

Elecrow Rotary Display

A unique circular touch display with a physical knob

Elecrow’s Rotary Display is available in 1.28-inch ($29) and 2.1-inch ($36) variants, combining a round touchscreen with a clickable rotary knob. Together, they can serve as a surprisingly useful companion for smart home automation controls, media control, and even creative work on your computer, besides being a fancy clock.

You can build your custom UI layouts using the LGVL graphics library or Squareline Studio’s UI builder tool. You can then flash them via Arduino or PlatformIO. With some PC-side automation, it becomes a compact controller for photo editing, audio mixing, or even video editing. While it’s a niche product, it is delightful to enhance your workflow.

reTerminal E1001 and E1002

A minimal read-it-later device or productivity dashboard

The reTerminal’s ESP32-based ePaper displays - monochrome E1001 ($79) and color E1002 ($109) - feature buttons at the top, a microphone, a buzzer, and a temperature and humidity sensor inside. While it’s not a Kindle replacement, you can use it as a basic eReader to catch up on RSS feeds or articles to read later without distractions. Alternatively, turn them into a productivity dashboard for to-dos, calendars, or simply display ambient information. And when it’s idle, it doubles up as a minimalist e-art frame to jazz up your room.

Elecrow CrowPanel Advanced HMI Display

Replacement of Google Nest Hub and Amazon Echo Show

Looking for a privacy-friendly alternative to the Google Nest Hub or Amazon Echo Show? The Elecrow CrowPanel Advanced Display panel ($60) is a strong contender to help you build just that. You can plug an external speaker and turn it into a hub with voice assistant capabilities. This display features an ESP32-S3 chip at its core, allowing you to flash ESPHome-friendly firmware and integrate it with Home Assistant. However, it’s not exactly a plug-and-play device, so you may have to add a speaker and tinker around to make it all work. Alternatively, you can use it to build something different, such as a picture frame or a mini arcade machine, as my colleague Adam Conway did.

Fun projects don’t cost that much

Most, if not all, ESP32 devices are cheap and allow you to tinker around to your heart's content. You don’t need high-end hardware to build smart-home tools, such as an offline assistant or a productivity companion. Whether you are creating a mini weather station or a custom smart display, there’s an ESP32-based device available to get the job done, and that too, on a tight budget.