It’s only available for specific regions and carriers in the U.S. and Canada. You’ll need iOS 10 or later. Turning on Answer All Calls as RTT/TTY, you won’t get voice calls anymoreIf you can’t hear audio during a call, click the microphone button to allow voice and text simultaneously.

The recipients can read the message immediately, as RTT (a more advanced protocol) instantly transmits your text into a voice message. Notably, you can only use RTT on iPhone using iOS 10 and later, provided your carrier supports the feature. So, let’s know the steps to turn on/off RTT or TTY on iPhone.

What is RTT and TTY on iPhone?How to set up and use RTT on iPhoneMake or answer RTT/TTY calls

What is RTT and TTY on iPhone?

RTT is a built-in accessibility feature on iPhone that provides a message box to send texts while making or receiving calls. It also uses automated transcription to convert audio to text and vice-a-versa. On iPhones, RTT/TTY doesn’t need any extra hardware. But if you have a real teletypewriter device, you may connect it through an iPhone TTY adapter. Interestingly, the feature also maintains the text records, so you can go through the conversation at a later date as well. Notably, software and hardware-based RTT/TTY calls are subject to regular voice call tariffs and rely on your network configuration. Different operators carry different variants of TTY/ RTT iPhone calls.

How to set up and use RTT on iPhone

Notably, when the RTT or TTY is turned on, you’ll see a special icon in the status bar.

How to turn off RTT on iPhone 

Make or answer RTT/TTY calls

Your receiver will see your message as you enter it if you choose to Send Immediately in Settings. If it’s disabled, complete your text and press the Send symbol. To transmit audio simultaneously, tap the mic icon. Furthermore, if you’re receiving an incoming RTT call (even if you haven’t turned it on), tap the RTT button to answer the call with RTT. The best part of RTT on iPhone is some built-in shortcuts like SK for “Ready to hang up” and GA for “Go ahead.” So, that’s all, folks! The built-in RTT/TTY feature of the iPhone is super helpful for people who face trouble in conversational calls and have to rely on communication assistance. If you have any queries, let me know in the comment section below. Read more:

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