As the document states, RCS will let you send larger messages up to 8,000 characters long (160 is the current limit). You’ll also getting typing indicators, read receipts, chat groups with up to 100 participants, high-quality photo and video sharing, WiFi chat without a cellular connection and larger file transfers.
If someone sends you a message using Chat and you don’t have the service yourself, you’ll just receive it as a normal SMS/MMS. Other upcoming features include “local sharing, mobile payments, sending audio recording, sending stickers and much more,” Verizon said.
Chat requires carrier support, and the service is already available in a limited way on Sprint and T-Mobile. Google has said that it will arrive to over 55 operators around the world, but hasn’t yet specified when. Verizon promised that it would arrive in 2019, so it appears to be coming early, provided you have Google’s very latest smartphones.