A developer created a WhatsApp bot using Twilio Functions and JavaScript to find nearby healthy restaurants based on the user's location data. The bot uses the Twilio API for WhatsApp to gather location data from users, and then makes an HTTP request to the Zomato API to retrieve a list of nearby restaurants serving healthy food. The bot responds with messages containing the name of each restaurant and a URL to get further details. The developer used Twilio Functions as they are easy to set up and run JavaScript code directly on Twilio, making it simple to integrate location data into WhatsApp conversations.