XIAO ESP32S3 3PCS Pack- 2.4GHz WiFi, BLE 5.0, 8MB PSRAM, 8MB Flash, Dual-core, Battery Charge Supported, Power Efficiency and Rich Interface, Ideal for Smart Homes, IoT, Wearable Devices, Robotics.

I converted 3 Levoit Air Purifiers (1 Core 400S & 2 Vital 200S units) over to ESPHome and they're all cloud free now. The Vesync integration for them works really well but I wanted cloud free control. Fun project. While you can reflash the existing Levoit boards, I opted to use Seeed Studio Xiao ESP32-C3 boards to bypass the internal built-in ones, so that I can easily switch back to factory control if desired. Super cheap and easy to set up in ESPHome Builder in HA. Here's a pic from one of my Vital 200S units. I 3d printed enclosures for each of the boards (blue square) and used some double sided tape to secure them. Using DuPont jumpers made it a super quick conversion.