Google is now completing the global rollout of its Rich Communication Services, popularly called RCS, to the Messages app on Android phones. The first effort towards expanding the release was towards the middle of 2019 when Google announced it will need to support a large number of carriers for the global rollout. RCS-based communication is similar to iMessage, supporting features such as typing indicator, read receipts, multimedia sharing in real-time, group messaging, and more. Besides these features, the Messages app is now testing end-to-end encryption for enhanced privacy.
To give you an explainer, the Messages app on your Android phone has so far supported text messages, emojis in pictorial format, and read receipts for carriers that allow that. Of course, you have the Multimedia Messaging Service, also called MMS, but that is extremely limited and is not common among users. MMS is also chargeable across carriers, which is why customers have refrained from using them to share media and other interactive contents. Their woes ended when dedicated apps such as WhatsApp entered the picture, allowing them to share anything freely over the internet free of charge. The only money customers had to spend was for the internet plan.
The Rich Communication Services were built by Google to improve native messaging on Android phones drastically, revamping the Messages app to support features that are available on instant messaging apps and Apple's iMessage. But since these services needed to be built from the scratch, it required the carriers to support such formats that can transfer over their networks. This is because all the data will need the cellular network to reach the other user, in a system that is based on IMS (IP Multimedia Subsystem).
This method is similar to how calls work on different networks but as far as messaging was concerned, it was not utilising the potential of cellular networks to the fullest. The full potential encompasses a data exchange system that dedicated apps such as WhatsApp, Telegram, or Facebook Messenger work on for communication.
All of the things that WhatsApp lets you do form the basis of what RCS is aimed at and the efforts behind it were spearheaded by Google. RCS is backed by a group of telecommunication companies and approved by GSM Association, the group that organises Mobile World Congress every year.
Google made sure telecom companies are indulging into making RCS a success despite the troubles these carriers expressed initially over the barriers in technology they possess and the technology they will need to acquire. Now that Google has cooperated with a large fraction of carriers in understanding RCS and implementing it for their networks across spectrums and regions, the tech company is moving ahead with the global rollout.
And now, Google is trying to assuage the concerns privacy advocates have favoured for a long time. The tech company is introducing end-to-end encryption for Messages so that the information that is shared between end-users remains private throughout the exchange process. Even Google or the telecom company that is providing RCS on your phone will not be able to intercept any of the contents shared between two individual users, thanks to E2E encryption.
Google will soon begin testing E2EE on Messages. In a post, the company has explained how end-to-end encryption will work. This will be meant for one-to-one conversations in Messages. To ensure E2EE, Google is using the Signal protocol.
For E2EE to work, both individual users need to be on the latest beta version of Messages and have the Chat over data or Wi-Fi feature enabled inside the Messages app. When the connection is successfully established, E2EE will become active. There will be a lock sign next to the text that reads "Conversation with XYZ". The encryption standard cannot be manually disabled but in case there is a barrier in the communication channel, it will be temporarily turned off.
The default behaviour for Messages here will be to hold the messages until end-to-end encryption is back but in case the sender wants the message to reach the recipient instantly, they can choose to send those messages as SMS, in which case E2EE will not be supported. Neither is it supported for MMS because of security standards this encryption protocol follows. But E2EE will work across devices and interfaces, including Messages on Web that can be opened inside an internet browser.
Well, nothing. I will suggest you wait for RCS to show up on your Android phone, post which you will be able to chat with other RCS users freely over an internet connection without paying any extra charges. I am not sure if your carrier will support all the features there are available inside RCS but you will surely get some of them, at least in the beginning.
For end-to-end encryption, you may try using the beta version of Messages app but I would suggest you wait for this feature to become available inside the Messages app in the stable channel.