I think we should do like Twilio
and Rename SMS to Message
as SMS is a bit confusing
see the note at the top of the page on https://www.twilio.com/docs/api/rest/sms
Not rename but add the Message API https://www.twilio.com/docs/api/rest/message, we need to keep SMS to keep backward compatibility and not make apps break. Please work on this once you're done with the SMPP Tests.