It might be this?Under Settings>Phone>TTY
what does it mean and what does it do?
don't bother, it would only work when dialing another TTY enabled telephone number. Basically what it does is work like an old dial-up modem works by sending the information over a standard telephone signal, to just send textual information. Yeah, it's essentially texting, but you can't just go and text anyone you want, because technically it still isn't texting. Overall, if you're not deaf or don't actively communicate with deaf people, and don't actually have any other need to use it, don't bother trying to use itshall i try it? lol