Embedded hardware
Lemon Box
A desk device that shows live crypto prices.
Problem
People check crypto prices on their phone 50 times a day. Each time they unlock, open an app, scroll, get distracted by notifications, close it. I wanted a small device on the desk that just shows the price. Always on. No browser, no notifications, no distractions.
Solution
I built a physical dashboard on an ESP32-S3 with a 480x480 round touch display. It shows BTC price and the Argentine dollar rate, updates live, and plays a sound when BTC moves more than 5%. You set it up by scanning a WiFi QR code on first boot. No cables, no terminal. Touch to switch between pairs. It just works.
How
ESP32-S3, LovyanGFX for rendering, PlatformIO for builds. CoinGecko and CriptoYa APIs. WiFi provisioning via captive portal. Touch gestures, I2S audio, NVS storage for settings. Open source on GitHub.
Outcome
A working device that sits on my desk and does one thing well. Public repo with full firmware and architecture docs.