What are the requirements for sending an MMS message from Vtiger CRM?

The following steps are involved in sending MMSes from Vtiger CRM:

• You need to sign up with a telephony service provider like Twilio. They will give you details like authentication ID, user ID, and password. 
• Once you receive the details, you must set up the service provider in Vtiger CRM.
• Your customer must have a phone number that can receive MMS messages.
• Once you integrate a service provider, you can send SMS messages to your leads, contacts, or organizations.

Note:
To send an MMS messages:

• You should have integrated Twilio as a service provider in Vtiger CRM.
• You should have an active Twilio account.
• Your contact should be able to receive an MMS message.