A 13 DOLLAR BOARD THAT SPOTS SMART GLASSES AND TRACKERS AROUND YOU
A 13-dollar board that tells you when a Ray-Ban Meta, AirTag, or license plate camera is nearby.
Open-hardwareSecurity
- difficulty
- ●●○○○
- time
- an evening
- license
- GPL-3.0
- repo
- repo ACTIVE322 stars
●●○○○ · an evening · GPL-3.0 · 322 stars · repo ACTIVE
WHAT YOU’LL NEED
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COMPAREE VERDICT
SquachWatch turns a cheap ESP32 display board (the creator's video says 13 dollars, the README says about 15) into a radio scanner that listens for known device signatures: Ray-Ban Meta and Snap Spectacles camera glasses, AirTag and Find My trackers, Samsung, Google and Tile tags, Flock license plate cameras, Axon body cams, Bluetooth card skimmers, Remote ID drones, Ring doorbells and hacking gear like a Flipper Zero. The 2.8-inch Cheap Yellow Display (ESP32-2432S028R) is the whole device: plug it into USB, flash it from a desktop browser, done. A watch list locks onto a known device, and hunt mode uses signal strength to walk you to a tracker. The one real trap is signature confidence: only 33 of 97 hardware prefixes are high-confidence matches, and exactly one of the 49 Flock prefixes is registered to Flock Safety; the rest are shared chip-maker blocks (Espressif, Liteon, Silicon Labs) that every dev board broadcasts. The firmware grades each signature and lets you filter by confidence, which keeps passing ESP32s in the log without crying wolf on screen. Flock cameras are mainly a US thing. The project is actively maintained (last push October 2026), well documented, and ships with a PC emulator you can drive in a browser before you buy hardware. If you want a pocket detector that is honest about what it hears, this is the one.
IN THE REPO
GOOD TO KNOW
- —Firmware in C++; the web flasher installs it from a desktop browser over USB, no IDE needed
- —Supports more than 15 ESP32 boards; the 2.8" CYD (ESP32-2432S028R) is the primary target
- —Every hardware prefix is graded against the IEEE registry: 33 high, 4 medium, 60 low out of 97
- —No schematic or PCB files — you buy a complete board
- —GPL-3.0 licence: commercial use allowed, modified firmware you distribute must ship with source under GPL-3.0
- —Over-the-air updates over WiFi on every board (Bluetooth on ESP32-S3 boards), signed releases, automatic rollback if a new version crashes
Parts to buy
3 itemsFrom our check of the build. Exact quantities and part numbers are in the creator’s BOM.
Can I build this?
Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.
Videos
I Made a $13 Surveillance Detector (And It Actually Works)20:45
The creator's own video about the detector, published 20 Sep 2026.
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Gallery
Start here
Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.
- 1.Flash the board (The web flasher works in desktop Chrome, Edge, Firefox or Brave. Pick your board from the list (grouped by family, or type the code printed on the back if unsure), plug it in with a data USB cable, click Connect & Install.)
- 2.Read the detection confidence table (33 high-confidence, 4 medium and 60 low out of 97 hardware prefixes. The README explains that only one Flock prefix is registered to Flock Safety and the other 48 are shared chip-maker blocks.)
- 3.Configure alert filters (ALERT FILTER (ALL / MED+ / HIGH ONLY), AUTO SNOOZE, TYPE FILTER, watch list. Set these before you rely on alerts.)
- 4.Optional: try the emulator first (Drive the firmware in a browser before buying hardware. Same code, rendered on PC.)
Resources
Documentation, files and community threads for this build — we link straight to the original sources and never rehost the creator’s files.
KNOWN ISSUES
- Only 33 of 97 hardware prefixes are high-confidence. Many of the rest are shared with ordinary dev boards. Use ALERT FILTER = HIGH ONLY or you will see false positives.
- Flock cameras are mainly a US thing. Only one of the 49 Flock prefixes is registered to Flock Safety; the other 48 belong to generic chip makers (Espressif, Liteon, Silicon Labs and others). The audit also removed a prefix labelled Vigilant that is actually registered to Sonos: for eleven releases every Sonos speaker in range was logged as a plate reader.
- The 2.8" CYD ships with two different screen drivers (ST7789 or ILI9341) depending on batch. A solid white screen means you flashed the wrong one; the web flasher has both.
- iBeacon detection ships OFF by default because one retail shop can flood the log. Turn it on in TYPE FILTER if you need it.
- SquachMesh TRANSMIT broadcasts a Bluetooth advert every 1.5 seconds with an address that never changes, which makes you trackable. It is off by default and the firmware shows a warning before you can enable it. DETECT mode is receive-only.
- Over-the-air WiFi updates need a saved network or one in range. A locked board ignores remote update requests. USB is always the fallback.
Is this legal?
The firmware is GPL-3.0: you may use and sell it, but if you distribute modified firmware you must share its source under the same licence. The device only listens to radio that gear is already broadcasting and does not break into networks, though it does send a few things itself (Bluetooth scan requests, a short WiFi visit at boot for the update check, and SquachMesh adverts if you turn TRANSMIT on). The creator's FAQ says plainly that he is not a lawyer, so check your local laws.
Which board should I buy?
The 2.8" CYD (ESP32-2432S028R) is the primary target, about 15 USD, and the board everything is designed on. The NM-CYD-C5 also scans 5 GHz. The LilyGo T-Watch S3 and S3 Plus listen to LoRa (Meshtastic and MeshCore), and the S3 Plus adds GPS for wardriving. The README lists more than 15 supported boards, several of them in BETA.
What does high vs. low confidence mean?
High: hardware prefix registered to the actual company (e.g., Apple for AirTag). Low: prefix registered to a chip maker that hundreds of devices share (e.g., Espressif for Flock). The README audited every prefix against the IEEE registry and rates each one. Use ALERT FILTER to decide what interrupts you.
Does it work outside the US?
Yes. It matches device signatures, not places, so AirTags and other trackers, camera glasses, card skimmers and Remote ID drones are found wherever they are. Flock Safety plate cameras are mainly a US thing, so outside the US expect few or none of those.
Can I build from source instead of using the web flasher?
Yes. Install PlatformIO, clone the repo and run `pio run -t upload`. A beginner-friendly walkthrough is in docs/BUILD.md.
What is SquachMesh?
Two SquachWatches in range draw each other's mascot on screen, can send encrypted messages if they share a five-word phrase, and support over-the-air squad updates. DETECT mode is receive-only; TRANSMIT mode broadcasts a stable identifier and warns you first.
Community builds
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Discussion1
FROM THE COMPAREE TEAM
33 of 97 signatures are high-confidence, and the project removed a Sonos prefix that logged speakers as plate readers for eleven releases. What would you set ALERT FILTER to first — ALL, MED+, or HIGH ONLY?
Talking Sasquach
GitHub user skizzophrenic, who publishes as Talking Sasquach. Built SquachWatch to detect surveillance devices and trackers in everyday environments, with community contributions from NitekryDPaul (Flock research), DH5DAX (LoRa driver and the ESP32-S3 WiFi fix), quietradio (NM-CYD-C5 port and 5 GHz scanning) and others credited in the README.
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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.
CompareeTEAM3d ago
Practical notes from our verification: the web flasher installs signed releases for most supported boards and works in desktop Firefox, Chrome, Edge and Brave (not mobile). The 2.8" CYD ships with one of two screen drivers (ST7789 or ILI9341) depending on the batch, and the flasher has both; a solid white screen means you picked the wrong one, so try the other. The signature confidence table is the most important thing to read before you rely on it: only one of 49 Flock prefixes is registered to Flock Safety, and the rest are generic Espressif, Liteon and Silicon Labs blocks that every dev board shares. The firmware grades each signature and lets you filter by confidence (ALL / MED+ / HIGH ONLY), which is the difference between a useful detector and one that cries wolf at every ESP32 in range. The creator explains the build in his own YouTube video (Talking Sasquach) and is also on Instagram as @talking_sasquach. The single biggest decision is not the board; it is whether you trust the low-confidence signatures or filter them out.