I had signed up for Telegram on a phone, so can't say whether you can sign up w/o a phone (I think it would require SMS verification).

It doesn't need you to be logged in on any phone however. You can use just the desktop app. In fact I am on some really crowded and hyperactive Telegram groups so can't even imagine keeping it on my phone. Besides not a single one of my IRL friends use Telegram. I see 3-4 names, maybe they had signed up once.

A smartphone isnt required, only a telephone number for authentification.

> A smartphone isnt required

It is for Whatsapp. Not only for sign-up, but actually all communication on the web version goes through the app running on your phone. The web "session" times out constantly, so I'd have to re-pair it with my phone all the time. If I still decided to use whatsapp.

To be really pedantic; a smartphone is not required for WhatsApp. You can activate a Google voice number with a landline, then use your Google voice number to activate WhatsApp running in BlueStacks or your emulator of choice.

Source: I did this for a few months. I'm not quite sure why...

A smartphone OS is required for whatsapp

> [A]ctually all communication on the web version goes through the app running on your phone.

How on earth does that work? Say my phone's on data, my laptop's on my home wifi with NAT. How does Whatsapp on the web reach my phone?

Your phone connects to WhatsApp's servers. So does your laptop. The bridging is likely done server-side. I assume this is done because WhatsApp is (probably) using end-to-end encryption, so everything must be ran by your phone (which is the only place where your private key is stored) in order to encrypt the messages.

It works impressively well, though -- I use it far more than I do the mobile client directly.

The problem is that you need to own that same phone number permanently. Phone numbers are tied to exactly one SIM card, which is tied to exactly one telco in one country. Too many ties.

Threema doesn't require a phone number but it's not free.

Depends on a country, in Sweden you can move your mobile number to any telco, and anyone can look up your number and your home address using something like [0]. But yes, it is still tied to a country.

- [0] https://hitta.se

Yes, what I meant to say is that the SIM card is tied to exactly one telco at any particular time. It's also tied to one device at a time.

Perhaps one of the virtual SIM card offerings would work with Signal though.

I'm juggling too many SIM cards and phones already. I don't want any new dependencies that complicate matters further.

You only need the sim card active to activate your signal with that number. After that you don't have to be connected to a cell network at all.

But I still need to keep the SIM card active or I could never switch phones (or reinstall the phone OS) without losing my Signal identity.

I cannot ever let go of the phone number I used to activate Signal. In practice, that means I need to keep paying for a phone tariff I may no longer want.

True. I was assuming most people have at least one phone number they want to keep long term (even if it's not always active with their cell). Note though that signal will also work fine with non-traditional services that provide free or much cheaper phone numbers like google voice (US), skype, or twilio.

It is true though that you do need to maintain a phone number. That is one of the trade-offs they made to allow it to actually be usable. I have not seen a better solution for encrypted communication yet.

How does the phone number tie-in make it usable? Phone numbers and SIM cards are about the most user hostile thing I can possibly think of.

What's wrong with the way Threema does it for instance, which is essentially to bind the identity to a key pair that you can back up?

Threema appears to optionally do the exact same thing. Signal eschews the flexibility to ensure more universal usability by being able to assume that anyone who uses signal can be associated with their phone number. An assumption that holds for the vast vast majority of potential users.

I don't see how making phone numbers mandatory makes Signal easier to use at all. There must be another reason for this restriction. Some say it's for spam protection.

Signal will work with Google Voice, but as far as I can tell you still need a smartphone to use it. Without that, you can't even set up an account because you need to scan an OCR code first.

No, you can change the number associated with your Telegram account.

I was talking about Signal. Sorry I didn't make that clear. The phone number is your identity. Changing it means reregistering with a different number.

[Edit] And I think it's essentially the same with WhatsApp, only they now make it a less manual process.

Ah, I should have mentioned that I was talking about Telegram in my original comment, too. Can't edit it anymore :/

In these cases you could use a https://jmp.chat/ phone number.

No smartphone is required for JMP, only an XMPP client (see https://news.ycombinator.com/item?id=16352711 for some client options).

A smartphone isn't required for Telegram either.

Incorrect. Whatsapp refuses to open on my iPad and isn't even available in the App Store. The only reason it got on there was a glitch in Apple's app sync which must've auto-downloaded it since I have it on my iPhone.

Sorry, I was talking about Telegram. Should have made that more clear.

You do need one to set it up, right? I had to scan a QR code displayed on my desktop with my phone. (I could continue to use the desktop app while my phone was being repaired, though, which was great.)

No, you can do the complete setup with the Telegram desktop app, but you need a device which can receive SMS or a phone call.

Oh hmm, looks like I got tangled in the threads - I thought we were discussing Signal. My bad!

Ah I see ;) Yeah the QR code scanning sounded like Signal / WhatsApp, never heard of that method in a Telegram app.

Wire doesn't. It uses the same protocol as Signal, has mobile, desktop and web apps and the source is on Github.

I'm using Signal on my linux desktop right now. It appears to be a packaged webpage but it works fine and is linked to my phone and laptop.

All it require is a phone number, besides it's Snowden approved :)

You're using signal in a browser on your linux desktop. Poke me when there's any way to connect via bitlbee or libpurple, like there is for ICQ, jabber, etc.

They lose all credibility when they force you to reveal your phone number. Doesn't matter who endorses it.

They are entirely honest about their trade-offs. While those trade-offs may be deal-breakers for you, it should bolster their credibility.