When we are developing something, I mostly prefer to keep the options open for the user. ** But depending on the development challenges, we can do: 1 - Have an option in the account online as Default Sender that will be enforced for when sending from CRM or other integratable apps 2 - If no Default is selected, the Ready to Use Options can show in dropdown in SMS Sending window on CRM and the user on CRM can choose a sender. Since some SMSes may require a cross communication between our end and the client/contact/lead