I need a basic proof-of-concept for a portable voice-recorder that is optimised for meetings and pairs with a simple Android companion app. Hardware • Suggest an affordable off-the-shelf microcontroller (Arduino, ESP32 or similar) with on-board Bluetooth. • Specify a low-noise microphone module, local storage option (micro-SD is fine) and a battery solution that will last a typical meeting. • Provide a concise schematic or parts list so I can order the components and assemble a test unit. Firmware • Record in standard WAV or MP3. • Expose Bluetooth commands for start, stop and file transfer. Android App (minimal) • Single-screen interface: start/stop recording, list stored files, download selected file to phone. • Target current Android OS version and keep code clean so I can extend it later. Deliverables 1. PDF/Breadboard schematic and parts list. 2. Firmware source code with brief setup notes. 3. Android Studio project that pairs with the device and performs the basic actions above. I’m happy to consider your preferred toolchain as long as the result runs on Android and the hardware remains low-cost and easily sourced.