Watchy: open-source ESP32 e-ink smartwatch
An open-source smartwatch with a 1.54in e-paper screen and ESP32, hackable watch faces in Arduino.
Photos
Photos: sqfmi/Watchy
Key Facts
- Chip: ESP32 (original)
- Display: 1.54in 200x200 e-paper
- Power: LiPo, deep-sleep between refreshes
- Framework: Arduino / PlatformIO
About This Project
Watchy is an open hardware smartwatch built around an ESP32 and a 200x200 e-paper display. Because e-paper only draws power when it refreshes, the watch can run for days on a small LiPo, and the community has produced hundreds of custom watch faces. Firmware is written with the Arduino framework, and the board exposes buttons, a vibration motor, an RTC and an accelerometer for step counting. It is sold as a kit, but the PCB and case files make it a good reference design for any low-power e-ink wearable.
Source & Attribution
Parts Needed
- Watchy kit from SQFMI (ESP32 + e-paper PCB, includes LiPo)
- Watchy case and strap (from SQFMI's shop or 3D-printed)
- USB data cable
Steps
- 1
Assemble the kit
Follow the official getting-started guide at watchy.sqfmi.com: connect the display's flex cable and battery, then fit the board into the case.
- 2
Install the Arduino ESP32 core
In the Arduino IDE, add Espressif's ESP32 board package and select the Watchy board (or ESP32 Dev Module with the settings listed in the guide).
- 3
Install the Watchy library
Use the Library Manager to install 'Watchy' along with its dependencies (GxEPD2, DS3232RTC, Arduino_JSON and others).
- 4
Flash a watch face
Open an example such as 7_SEG or Basic from the Watchy examples, connect the watch over USB, and upload. If it's in deep sleep and won't connect, hold the reset buttons as described in the guide.
- 5
Set time and weather
On first boot, use the on-watch menu to connect to Wi-Fi so it can sync the time. Weather faces need an OpenWeatherMap key in the sketch settings.
- 6
Tips
Every watch face is a small class that draws on the screen, so you can copy an example and edit it to make your own. The Discord is the main place for help.
| Part | Qty | Role | Est. Price | Buy |
|---|---|---|---|---|
Watchy kit (ESP32 + 1.54in e-paper PCB) Sold as a complete kit by SQFMI | 1 | main board | — | — |
| 1 | power | $4–$10 | View |
Not included: 3D-printed case, wire, solder, USB cable
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