My application needs to verify phone numbers that are provided by the user. What is the absolute cheapest way to send an SMS to a phone? Which company/API should I go to? I'm not looking for a hack solution to send out 10 SMS a month kind of thing, I need to roll this out for a company that will be sending mass amount of verifications. But they want to do it at the lowest cost. (Each user will only need to verify once)
Sorry forgot mention the SMS needs to be international