Twilio's support for the WhatsApp Business API is now Generailly Available! In addition to meeting Twilio’s SLA standards for GA products, this change represents an improvement in the product experience, support and resilience, as well as a commitment to offer WhatsApp as a first-class citizen across Twilio products.
To try WhatsApp, head over to Twilio Sandbox for WhatsApp. To get your own number, follow the onboarding instructions to connect your WhatsApp number. Once you are live, you can send and receive WhatsApp messages using the Programmable Messaging API or the Conversations API.