Creating a Low-Cost e-Paper Smartwatch with ESP32

With the development of technology, the watches we wear now have far surpassed the original function of telling time. Counting steps, heart rate monitoring, connecting to a phone to make calls… As functions increase, performance strengthens, and screens improve, the price of watches has also risen.

For those who only need the basic functions of a watch, the project we are introducing today may interest you.

Today, we are introducing the qpaper, an ESP32-powered e-Paper smartwatch that is affordable and customizable.

The core of qpaper is the LILYGO T-Wrist E-Paper 1.54 Inch Display, which is a great platform for building a low-cost smartwatch. The price of the watch ranges from 13 to 26 dollars depending on the options. The ESP32 serves as the main controller, can run custom software, and has Wi-Fi and Bluetooth capabilities. Additionally, the low-power E-Paper screen means the display can always be on.

Creating the qpaper watch also requires some extra work. First, the Reddit author qewer3333 created CAD design files to produce a transparent UTR-8100 resin 3D printed case, installed the watch and a 250mAh battery inside the case, and then attached a standard 22mm iWatch-style strap.

To drive this watch, the author also developed an operating system called qpaperOS (open-sourced on GitHub), which is still in development (based on the espressif-esp32-arduino framework and PlatformIO).

The firmware has multiple implemented functions such as displaying time and date, battery percentage, power-saving mode, applications and application systems, GPS functionality, weather display, etc.

To save power, the ESP32 enters deep sleep mode, waking up every minute to update the time displayed on the screen. In this way, qpaper can run continuously for five days on the selected battery.

For more details on how the firmware works, you can check GitHub (https://github.com/qewer33/qpaperOS).

qpaper provides a great option for those looking for a low-cost, long battery life smartwatch (we won’t mention the ones that need to be charged daily). You can customize it according to your specific needs by modifying the open-source qpaperOS operating system. All source codes and material lists can be found on GitHub.