You can use Signal between Android and.iOS, i know this as I (android user) use it all the time to msg contacts using Signal on their iphone, don’t use RCS ffs.

They should’ve worked to use xmpp or matrix as their replacement for SMS, but they chose an alternative that let’s corpos run servers and not anyone else.

Fucking garbage technology.

Last I checked, there is still no way for developers to use RCS on Android, so it’s a non-starter for me. I do not and will not limit myself to first-party apps.

Please correct me if I’m wrong. If there’s an open-source RCS-compatible messaging app out there, I’d love to try it.

RCS is even less secure than SMS though — it’s unencrypted and by design, Google, Apple and the carriers all have to be able to inspect the content. And the way it’s designed makes it really difficult to have an open E2E encryption standard. So as a result, Google<->Google is encrypted, Apple<->Apple is encrypted, but combine even one device not of the same type in a group chat and it has to be unencrypted.

Any FOSS apps on Android that support it? Even Google Voice (which I use for work) doesn’t seem to support it. I still get messages like “so and so reacted to your message”.

Now its not just the carriers now get your texts unencrypted, apple and google do too.

Use matrix, XMPP, or simpleX if you want something private.

Does iOS use RCS everywhere, or only if your and/or the recipient’s phone carrier are specifically supported?

It’s nice that Androids can finally send me high quality images and participate in group chats without as much jank. Still not as good as an iMessage group but a lot more bearable.

The people I know with ios still haven’t figured it out.

Alternarive to SMS maybe. No alternative to chat apps, because carrier-controlled.

I don’t think I can use it on my phone since it’s too old…

A good rule of thumb is : does any of the participant maintain the backend?

If not then you are dependent on at least a 3rd party. If that 3rd party is not entirely open, meaning at least

• standards for the protocol,
• open source for the backend and frontend,
• alternative clients,
• alternative backends,
• both can be actually used (not just in theory because the protocol has been published)

then basically you should consider that this 3rd party owns your group, there is no expectation of privacy in it, it can be closed in an instant, messages can be modified without you knowing it, etc.

TL;DR: bad.

AFAIK there’s no free as in freedom implementation and only works with propriety apps and I read google messages refuses to use RCS on rooted/unofficial systems. So that’s a big no.

Another big problem is, people who don’t have mobile internet and unknowingly have it enabled (aka most people who still use SMS) won’t get the message until they connect to WiFi or some time passes.

i thought it was stupid before, and I still do

My VPN doesn’t work with RCS, which is, at best, annoying. It automatically connects when I’m on untrusted WiFi. Hopefully anyone messaging me has the “fall back to SMS” option enabled, but I’ve learned that several don’t. I learned that because I didn’t get texts from them until after I left work, (and disconnected from the work WiFi).

Even worse, group texts don’t have any option to automatically fall back. So I don’t receive any group texts at all while I’m at work, but the senders have no way of knowing that. In fact, there have been several instances in recent memory of friends/family being left out of the loop on plans, because they weren’t receiving RCS for some unknown reason, which meant they missed an entire group text conversation.

My father’s phone is particularly bad about it. It’s an iPhone, and he’ll just randomly stop receiving RCS until he toggles his cell service off and back on again via airplane mode. But who the hell would think to toggle airplane mode, when there is no indication that they aren’t receiving something? It’s a catch-22, where he doesn’t get any notification that something is wrong, because he doesn’t know he’s supposed to be getting notifications at all. There’s no way for him to prove a negative, so the only way for him to reliably get RCS is to toggle airplane mode every few minutes. Which isn’t really a feasible use-case scenario.