title: Phone Number Verification System via SMS
body: <p>I am building a backend where i need a way that users can verify their phone numbers, or even authenticate via phone number. After a bit of research i realised that twilio is generally a great choice but outside of the US, it's almost unpayable, as i would pay a minimum of 0.092$ per SMS in my country. If i would use their verify service it would cost another 0.05$ per successful verification. On every phone provider's contract here in my country you get at least 1000 SMS for free per month. Why is that even so expensive when you do it with 3rd party providers?</p>
  <p>How do big companies like Uber do that? Uber is also available in my country, but i could for example login/logout multiple times a day, and they would have to send a SMS to my phone number every time.</p>
  <p>Basically my question is, if there is a way to implement a phone number verification system without the hilarious costs?</p>