Custom ESP32-C3 firmware turns the $70 Xteink X4 e-paper reader into a general-purpose wireless hacking and utility device with 40+ apps.
Key Takeaways
Forked from CrossPoint Reader; inherits full EPUB 2/3 rendering, KOReader Sync, and Calibre transfer while adding offensive/defensive wireless tooling.
Hardware: ESP32-C3 RISC-V at 160MHz, 380KB SRAM, 16MB flash, 4.26” 800x480 e-ink, BLE 5.0 + WiFi on shared radio, MicroSD, 7 physical buttons.
Recon tile is passive-only (PCAP recording, probe sniffing, wardriving, deauth detection); Offense tile covers beacon flood, SSID clone, BLE spam, and DuckyScript over BLE or USB.
Defense includes Ghost Mode (MAC rotation + RF kill in one action), AirTag/SmartTag tracker detection, SD encryption, duress PIN, and Emergency SOS mesh beacon.
Activity-based UI architecture: every screen is an Activity subclass managed by ActivityManager; RadioManager arbitrates the single WiFi/BLE radio.
