Imessage for iPhone? Is the phone off?

Ok so basically I know that when you text an iphone to iPhone it will says "message delivered" and if the phones off, it says sent as text message. So when I call this person it goes straight to voicemail. (As if the phones off right?) but yet I text and it says message delivered as if the phones on. Anyone know whats going on? Cuz I always assumed if the phones off it wouldn't say message delivered. Thank you!

Hi i have an iphone aswell

So basically even if the iphone is off you can still text as imessage but you need to have internet connection if you want to send it as an imessage, so maybe the reason it said sent as text message was because you had no internet, it doesn't matter weather the phone is on or off.

so what happened (assuming you don't have internet 24/7 on your phone) is that you sent a message to someone who had there phone off and it said Sent as text message… But that might have been because you didnt have internet at that time, not because the persons phone was on or off. And then when you called that person it would go to voice mail coz the phone was off… But you can still text someone when the phones off and you must have had internet connection if it said 'message delivered.

So to sum up it doesn't matter if the phone is off or on when texting, it was down to your internet because to send as imessage you must have internet connection, and if you don't it will automaticly send as normal text message.
but when phone calling if the persons phone is off it would go straight to voicemail like any other normal phone, but you can still text the person whos phone is off, they will just get it when they turn on the phone again.

Hope this wasn't to confusing i tried my best to explain and i hope i helped xx: D

ps don't mind my spelling and puncuation:)