I honestly don't understand why anyone cares about this so much: how often usb your phone out of batteries and without Internet but you have another device with both Internet and power? I have already been using WhatsApp without issue from my desktop using their downloadable apps for years.

The current architecture is great: I have a single source of trust holding my encryption keys and a single place where I know all of my chats are being archived so I in turn have a single place I can backup and know I have a fully consistent history.

You know what I do want? I just want them to make their desktop app work on iPads and iPhones, so I can use my other phone or--and this seems like it should be "big" for a lot of people (and even sounds like the actual use case at least one person in this thread is excited about)--a tablet to access my account and full chat history.

This doesn't require any changes to their architecture, nor does it require them to do any complex encryption shenanigans they didn't already figure out; it doesn't break the "single source of truth" maxim that WhatsApp currently is best-of-breed at, and particularly for tablets it should be easy as AFAIK their desktop app is just an Electron app anyway: it couldn't take more than a week to port it!

And once you get the desktop app running on other phones, I claim you have solved at least 90% of the actual use cases people have had for "multi-device" for years.

The only case it doesn't handle, again, is the case where my phone is out of either battery or Internet and yet I have another device that has both... which is so rare in the lives of most of the people I know as to call into question the importance of waiting years to satisfy the 90% case of "I just want to use my iPad or my other phone to access my account while my normal phone is downstairs or at home or in my pocket... with Internet and power".

And OK: I know someone is going to now whine "well I had that situation come up once" or even "that happens to me all the time", but I want you to really sit back and think how often that happens, how likely it was, how common it is, and how avoidable it could be... I claim you would have to admit it is actually at best kind of a "you thing" that you have somehow have Internet access and power that you can't share with your phone.

As remember, and it sucks that I feel a need to underscore this: the current WhatsApp desktop experience doesn't require you to ever touch your phone. I am not claiming "just use your phone": I am saying that if the desktop "remote access to your account" app were running on your iPad and your other phones, it would almost certainly cover almost every use case you have...

...and that WhatsApp could have easily done that years ago, but for some reason they chose not to, which makes absolutely no sense to me as it is clearly trivial to do (and in fact people have built third party apps from scratch to do it over the same protocol with tiny teams of probably one person, and yet WhatsApp so far had not).

And if you haven't tried the desktop experience of WhatsApp: do it! It is actually really awesome. I am certainly not claiming it is perfect, and I am sure someone is itching to tell me of the time the app spazed our and all the chats appeared in the wrong order or it refused to connect to their phone until they re-paired it... but if you honestly compare it to pretty much any other chat app's desktop experience, I think you will have to admit that it is at least as good as even the best of them, with the only limitation hat your phone technically has to be "on" somewhere (which I will again claim is a minor inconvenience as you probably want your phone to be on for a number of non-WhatsApp reasons).

The only thing about it that actually limited use cases people seem to commonly have is that it doesn't run on mobile devices: if it did, I think most of this work would have seemed like a waste of time targeting a small niche use case (if what was already a niche use case, as I think most people only own a single phone anyway).