&gt; [SMS] is the only thing left that can communicate with everybody.<p>Except for when it does not. More often than not carriers don&#x27;t return the correct status codes, marking messages as delivered when in fact the recipient does not even have SMS enabled in their contract. This gets even worse with international messages that can be routed through multiple carriers&#x27; networks until they reach (or don&#x27;t) their final destination.