AWS SNS SMS seems best suited for internal communications (we use it for alerts); it does not seem suitable for commercial use where you require targeted sends, you'd have to create a topic for each customer.
Source: use it and twilio.
Source: use it and twilio.
Looks like we'd need https://docs.aws.amazon.com/pinpoint/latest/userguide/channe...
Which isn't bad, but is much more limited than what Twilio provides.