[toast0]

> In my humble opinion, having used Twilio extensively for over a year, it is an awful service.

> They will happily take your money and report that SMS are being delivered when they're not.

This is an industry issue. You can request SMS delivery indications, and the carrier can send you delivery indications while dropping the messages. Or an intermediary might do the same thing. There's no way to ensure you only get delivery confirmations from the phone, so the delivery confirmation doesn't mean much. (Often, requesting confirmation results in better deliverability though)

If you can track delivery yourself, because a user is expected to use the message right away (verification), you should really be running multiple providers and picking the provider to use based on success and costs.

All the sms providers will tell you that they have global coverage, only use direct routes, and that they're the best. But they're all lieing. I ran a global SMS (and voice) verification service with 5 SMS providers, and when a major provider had a big outage, their success graph went to zero, but every other provider's graph dropped significantly too --- they all had some routes through that provider.

[csharpminor]

Yeah the underlying issue is that telecoms networks naturally trend towards monopoly. So often times there will be only one route that is cost effective / reliable to deliver traffic.