BUILD YOUR OWN E-PAPER SMARTWATCH FOR 60 DOLLARS — THE BATTERY LASTS A WEEK
An ESP32 smartwatch with a week-long battery, dozens of community watch faces, and a case you print — if you are willing to solder and code.
by SQFMI
Open-hardwareDisplays
- difficulty
- ●●●○○
- time
- a weekend
- license
- MIT
- repo
- repo ACTIVE2,771 stars
●●●○○ · a weekend · MIT · 2,771 stars · repo ACTIVE
WHAT YOU’LL NEED
- 3D printer + filament — printable parts — files are in the repo
- Electronic parts — full list with part numbers in the repo BOM
- Dev board / microcontroller — runs the project firmware
Partner
COMPAREE VERDICT
Watchy is exactly what it says: a fully open smartwatch kit built around an ESP32 and a 1.54-inch e-paper display. The e-paper draws almost nothing when idle, so a single charge lasts about a week. You get Bluetooth notifications from iOS or Android, step counting, and RTC timekeeping. The catch is assembly: the kit ships as bare PCB and components, so you need to solder surface-mount parts or buy a pre-soldered version. Once built, you flash watch faces via USB-C using the Arduino IDE. The library of community faces is large and the code examples are clear, but if you have never touched Arduino, expect an evening reading docs before your first custom face works. The 3D-printed case is functional but not polished — it looks like a maker project, not an Apple Watch. If you want a hackable wrist computer and you are comfortable with a soldering iron and basic C++, this is a real weekend project with a useful result. If you expected plug-and-play, buy a commercial smartwatch instead.
IN THE REPO
NOT IN THE REPO
- —Complete hardware files (schematic, PCB layout, 3D-printable case STLs) in the repository.
- —Bill of materials provided; official shop sells kits for around $60 plus shipping.
- —Firmware is Arduino-based; example watch faces and libraries are in the repo.
- —MIT license — commercial use is allowed.
- —Documentation covers flashing, watch face development, and hardware assembly.
- —No pre-soldered kit option — you must assemble the board yourself or buy a fully built unit.
Can I build this?
Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.
Partner · KickstarterHeyGears G1: 10M+ colors and transparent parts in one print, plus UV printing on flat objects. Figures, parts and labels — no painting.
Videos
This DIY Open Source E-Paper Smart Watch Is The Coolest! Watchy ...
No official build video from SQFMI. Community walkthroughs exist on YouTube but were not provided in the payload.
Gallery
Start here
Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.
- 1.Read the Quick Start guide in the repository wiki to understand the assembly and flashing process. (Start here before buying anything — it will tell you whether you want the bare kit or a pre-soldered board.)
- 2.Decide whether to buy the official kit from sqfmi.com or source components yourself using the BOM in hardware/bom.csv.(The official kit is the easiest path; self-sourcing saves a few dollars but adds lead time.)
- 3.If you bought a bare kit, solder the components following the assembly notes in the docs folder.(Surface-mount work is required; if you have never soldered SMD parts, practice on a throwaway board first.)
- 4.Print the case and buttons from the STLs in hardware/Case_3D_Print; PLA works fine.(The case is designed for FDM printers; supports are minimal. Budget 12 hours print time.)
- 5.Install the Arduino IDE, add the Watchy board definitions, and flash one of the example watch faces from examples/ to verify the hardware works.(The repo includes a detailed setup guide in the docs. USB-C cable required.)
Resources
Documentation, files and community threads for this build — we link straight to the original sources and never rehost the creator’s files.
Partner · KickstarterBluHub reads and burns Blu-ray/DVD/CD, adds USB-C, USB-A, SD/TF and 10 Gbps data — plug and play, grand-piano finish.
KNOWN ISSUES
- Buying the bare kit without SMD soldering experience — the ESP32-PICO-D4 has a fine-pitch QFN package and will waste your weekend if this is your first surface-mount project.
- Forgetting to charge the battery before first power-on — the e-paper will not initialize if the battery is too low, and you will think the board is dead.
- Expecting a polished consumer product — the 3D-printed case looks handmade, the screen refresh is slow, and the software requires reading docs. This is a hacker watch, not a Fitbit.
- Not checking the community forum before writing custom code — common problems (sleep current, RTC drift, Bluetooth pairing) have been solved dozens of times and the answers are in GitHub issues and Discord.
- Printing the case in the wrong orientation — the STLs have specific print directions for strength and finish; read the notes in the Case_3D_Print folder before starting the print.
- Assuming iOS feature parity — you get notifications on both platforms, but replying to messages only works on Android because of iOS limitations.
Do I have to solder the kit myself?
Only if you buy the bare kit. Pre-soldered boards are available from the official shop and some resellers, but they cost more. Check sqfmi.com for current options.
How hard is it to write a custom watch face?
If you have written Arduino sketches before, it is straightforward — the examples in the repo are well-commented and you mostly call library functions to draw text and graphics. If you have never touched Arduino, expect a few hours reading tutorials first.
Can I use this as my daily smartwatch?
Yes, but set your expectations: you get notifications, step counting, and timekeeping. No touchscreen, no app ecosystem, no heart rate monitor. It is a maker-friendly notification wrist display, not a fitness tracker.
What is the actual battery life?
Around a week with typical use (checking the time a few dozen times a day, getting a handful of notifications). Heavy Bluetooth use or frequent screen refreshes will drain it faster; light use can stretch it to ten days.
Community builds
No community builds yet — be the first, we feature the best ones.
Discussion1
FROM THE COMPAREE TEAM
Over 2,100 stars and a library of community watch faces — what would you code for your wrist first: weather, crypto prices, or something entirely different?
SQFMI
SQFMI is a small hardware studio focused on open-source e-paper devices. Watchy started as a project to build a hackable smartwatch that anyone could modify, and it grew into a platform with an active community contributing watch faces and code libraries.
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DISCLAIMER
- Comparee is not the author of the projects featured here. All rights to each project belong to its creator — every page links to the original source, and we never host creators’ files.
- Information is provided without warranty and may become outdated as projects evolve. Prices are indicative bands only — always check the creator’s parts list for current costs.
- Building and operating any project is at your own responsibility. Protective equipment, safe workshop practice and compliance with local regulations are the builder’s responsibility.
CompareeTEAM24d agoedited
Practical notes from our verification: the repository is active and well-maintained, with regular commits and a responsive community. The Discord is the best place for troubleshooting — GitHub issues are hit-or-miss. The biggest trap is buying the bare kit without realising you are signing up for surface-mount soldering; if you have never done SMD work, the pre-soldered option is worth the extra cost. The case prints cleanly on any FDM printer, but the finish is obviously DIY — sand and paint if you want it to look polished. The watch is genuinely useful once built, but it reads as a maker project on your wrist, not a consumer product.