We are looking for a service that will provide API to help us build Group MMS Chat Bot for our client. We already have a working solution built on Twilio as 1-on-1 SMS/MMS chatbot using webhooks and our backend handles all the logic behind. And we would like to extend this solution to fully support Group MMS features.
How can we obtain access to your sandbox API to try out those features of having multiple recipients in a single inbound/outbound MMS message?
Also, it is said that it is possible to register a free developer account to try out the API, but I'm still receiving that CreditCard_Auth_Form each time I'm trying to register as a developer. Should it be this way?