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Comment by Veratyr | Hacker News Reader

Has Signal fixed the multi-device issues (like not being able to use multiple Android devices)? Last I checked having multiple mobile devices was impossible.

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No but neither does WhatsApp. The reason for this is that it's incredibly hard to properly do end-to-end encryption with multiple devices. It's a trade-off you have to accept if you want secure end-to-end encryption.

The way it works with WhatsApp and Signal is that your key is generated on your phone and never ever leaves it. The web client actually establishes a connection to your phone and routes all messages over it.

Now, the Axolotl ratchet protocol does support encrypting messages to multiple keys (it's what they use for group chats), but doing it properly requires time and effort in order to remain secure.

We've solved the multi device issue at Wire (wire.com). Causes some challenges - larger payload, not super fast performance in browsers once you hit certain level of connections and messages, but very, very usable.

wire.com/privacy for security whitepaper.

I know WhatsApp doesn't do it but proper multi-device support is something I require to move. At the moment I just use a private XMPP server so while it isn't technically "end-to-end", it's practically end-to-end as I control the server.

I do that too, but it doesn't work outside of a close group of friends.

For me, multi device support is not important since I have my phone with me all the time, and if I'm on my laptop there's the web client.

Apparently XMPP with Conversations + OMEMO provides secure multi device support, haven't tried it though and I'm not sure if I could get any of my non-tech friends to use it.

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