Learn how to flash custom firmware like ESPHome and Tasmota to a Sonoff S31 smart device in this comprehensive tutorial video. Discover the benefits of custom firmware, explore alternatives, and follow step-by-step instructions for disassembly, GPIO pin identification, and connection to a USB flasher. Gain insights into firmware selection, flashing processes for both ESPHome and Tasmota, and device reassembly. Explore Home Assistant integration, including onboarding, entity management, and automation setup. Get detailed information on required parts, tools, and additional resources for further learning. Perfect for smart home enthusiasts looking to enhance device functionality and integration with Home Assistant.