I am following the instructions on https://www.twilio.com/help/faq/sms/can-i-try-twilios-global-sms-without-upgrading
However, in Step 2 Give your account calling permission, the countries are quite limited. Does this mean that I cannot set up my Twilio API with a USA number and text to Thailand? It appears that texting to Thailand is not the issue, but rather the ability to call to verify the number to begin with.
In Step 3, "Verify the phone number where you will be sending SMS messages." Does this mean that I can only text to numbers that have been manually verified through this website? What if I want to import a spreadsheet of my contacts that I want to send SMS to? It would be nice to be able to enroll new numbers via an API.
Finally, does upgrading help any solve any of these roadblocks to send SMS from USA to internationally? If not, any recommendations of other services with good APIs?
Thanks for reading and pitching in!