Apple Watch accessibility features include RTT calls — Here's how it worksYes, you can use RTT on your Apple Watch
On Apple Watches with cellular, you can use real-time text or RTT. The protocol transmits audio as you type text. Ideally suited for those with hearing or speech difficulties, RTT lets you communicate when you're away from your iPhone using built-in Software RTT that's configurable in the Apple Watch app.
Apple explains:
RTT is not supported by all carriers or in all regions. When making an emergency call in the U.S., Apple Watch sends special characters or tones to alert the operator. The operator's ability to receive or respond to these tones can vary depending on your location. Apple doesn't guarantee that the operator will be able to receive or respond to an RTT call.
Using RTT on Apple Watch
Here are the steps to activate and use RTT for conversational text calls on your wearable device when you're away from your iPhone.
Turn on RTT
Tap on the Apple Watch app on your iPhone.
Under the My Watch tab, select Accessibility.
Tap ...
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Apple Watch accessibility features include RTT calls — Here's how it works