Yeah... I just started getting back into building sms/mms/rcs apps on Android and oh boy. It's much more of a mess than I expected, and much more "oh so it's basically just Google now, and they seem to be trying to lock it down further" than I expected (or hoped).

And you can't even implement it yourself because it requires special permissions on Android, which you can only get if you're a carrier/oem-blessed app. And the early "you'll be able to build other apps, there will be an API like this: https://github.com/android-rcs/rcsjta" promises (which would put it on par with sms/mms) never materialized, despite a reference implementation that did exactly that over a decade ago.

At this point I'm just totally against RCS and I'm intentionally turning it off. Why hand all of your messaging communications over to Google, when they've got such a consistent history of being hostile? We're much better off going back to telling people not to use sms (or mms or rcs) at all because it's insecure.

> And you can't even implement it yourself because it requires special permissions on Android

That depends on your carrier, which is even worse. There are several ways to activate RCS for a phone number, as this standard is meant for carriers rather than app developers, and the carrier gets to choose which one they want.

I think the reference implementation died around the time carriers shut down their RCS servers because nobody was using them. https://github.com/Hirohumi/rust-rcs-client seems to be the most reason open RCS client at the moment (with an Android demo app).

The real need and opportunity for an RCS messenger is on the LineageOS/custom ROM scene, where these permissions are available (you can sign the ROM yourself, after all).

As for the Google stuff, RCS being routed through Google is an anomaly that will hopefully be fixed as carriers add support to it so native Android <-> iOS messaging isn't completely terrible. Progress has been slow outside of countries that still use SMS (like the USA) but eventually we'll be back to normal carrier-based carrier message exchange once things calm down a bit.

On the Android side of things, I don't expect things to change soon, as most of the restricted fields were at one point available to developers and were mostly used to stalk users across installs without their knowledge for tracking and "telemetry" purposes. A country where people actually use SMS/RCS will have to crack down on Google's lack of an RCS API.

My novice read of it is that Google made the mistake of trying to hand off the management burden to carriers, since they felt that the way to make something universal like SMS/MMS is to include carrier support.

But that obviously didn’t work because there are hundreds (thousands?) of cellular carriers around the world and they are the wrong people to manage such a thing.

So they basically are steering it back to “Google’s shitty iMessage.”

The universal thing isn’t the carrier anymore, the universal thing is the Internet that runs on top of it, which is perhaps why just about everyone outside the US tends to use messaging apps like WhatsApp/Signal/WeChat/etc.

Then in practice it’s just Whatsapp owned by Meta