DIY Air Quality Station with ESP32-S3 and second-hand 4.2" E-Paper — No App Needed [NO TALKING]

Ever wanted a screen that shows real-time air quality without draining a battery or needing an app? In this ESP32-S3 tutorial, I build a low-power air quality dashboard using a 4.2" e-paper (e-ink) display, the GxEPD2 library, and the free WAQI API. This is a complete, beginner-friendly walkthrough — from wiring the SPI e-paper module to ESP32-S3, to parsing JSON air quality data, to rendering a full dashboard with AQI, PM2.5/PM10, temperature, humidity, and a 7-day forecast chart, all in Arduino C++. ✅ What you'll learn: Wiring an SPI e-paper display to an ESP32-S3 Installing and configuring GxEPD2, ArduinoJson, and U8g2 for Chinese/Unicode fonts Fetching and parsing live JSON data from the WAQI air quality API Drawing a custom multi-panel dashboard (AQI box, metric grid, forecast bar charts) Power-saving tricks for e-ink displays (deep sleep, powerOff logic) Troubleshooting common issues: white screen, garbled text, WiFi failures 📦 Full source code: https://lingflux.com/en/experiments/e... If you're into ESP32 projects, embedded systems, or low-power IoT builds, this one's a great weekend project. Drop your questions in the comments, and if you'd like more ESP32 and e-paper tutorials like this, subscribe and hit the bell so you don't miss the next build!