Twilio knows which numbers will charge customers, THEY HAVE THE DATA. They can make a list of numbers that charge customers, and then have a flag that disallows SMSes to those numbers.
They also have relationships with phone providers in every market that they are in, and those providers can provide that same information and then allow a blacklist to those numbers or whatever format the premium numbers occur in.
It's not hard at all. It's a nice value-add feature and I'm sure if a competitor like MessageBird implemented something like this, it would be an easy differentiator if Twilio doesn't want to provide this.
Twilio knows which numbers will charge customers, THEY HAVE THE DATA. They can make a list of numbers that charge customers, and then have a flag that disallows SMSes to those numbers.
They also have relationships with phone providers in every market that they are in, and those providers can provide that same information and then allow a blacklist to those numbers or whatever format the premium numbers occur in.
It's not hard at all. It's a nice value-add feature and I'm sure if a competitor like MessageBird implemented something like this, it would be an easy differentiator if Twilio doesn't want to provide this.