But since SMS is not a sure thing, it's possible for such to get lost forever. And here on just a few phones from one network to the next I've seen messages arrive with a time before it was sent as well as long delays of 10 or more minutes.
What I'm getting at here is a question. Were you thinking that this was reliable?
This is my understanding:
If someone's phone is off/dead than if you send them an SMS, it will not be delivered until they turn their phone back on. So it's safe to assume that if the sent and delivered times you see on your phone in the message you sent are the same, that their phone received the message when you sent it. Is this corrrect? And does anyone know if this is true for all phones/service providers?