This project involves building a smart doorbell using Twilio and Android Things. The backend is built using Node.js, which interacts with the Twilio API to make calls when someone presses the button on the doorbell. The Android application runs on an Android Things-enabled Raspberry Pi and uses Retrofit to communicate with the Node.js backend. When the button is pressed, the app makes a request to the backend's "/call" route, which initiates a call to the Twilio number associated with the user's phone. The call includes a voice message saying "There's someone at the door." The project also uses ngrok to forward the Node.js server to a public URL, allowing it to be accessed remotely. The application is tested by running it on the Raspberry Pi and pressing the button, which logs a message in Android Monitor when pressed. Finally, the app makes an MMS request using the camera module to send a picture of the person ringing the doorbell to the user's phone.