Developer's DescriptionBy AT&TContinue the conversation, wherever you are.Continue the conversation, wherever you are. AT&T Real-Time Text (RTT) helps AT&T customers with disabilities communicate over the wireless network as an alternative to TTY (TeleTYpewriter). RTT uses a free-flowing mix of text and voice conversation, so as quickly as characters are typed on the sending device, they are displayed on the receiving device.RTT is a separate service from traditional text messaging (SMS).Great for everyday communicationSupports 711 and 911 callsEliminates the need to connect to mobile TTY devicesWorks on the AT&T cellular network and over Wi-Fi CallingOffers a more natural, conversational flow compared to TTY and relay service for persons who are deaf, hard-of-hearing, or have speech disabilitiesSupports simultaneous text and speech on RTT-to-RTT callsAutomatically imports contacts from your phoneWorks on Android Smartphones and tablets operating system 4.4 and up;[1]Data and voice rates may apply for app download & usage.