A chat that can only be accessed using a protonmail account and (not web based) can be installed on multiple operating systems (Windows, MacOS, Unix). All applications must be closed in order to login to an online chat to prevent screen captures, copy/paste, etc. Simplistic yet attractive chat interface. You must possess a predefined key as well as your own proton mail account to access a chat. The keys would be generated via protonmail application with a partner or group. The user logs onto the protonChat application in Windows, the app proceeds to close all other applications (browsers, other chat apps, etc), mainly non-essential things. After it is confirmed that everything is secure, it brings up an interface where you input said key and your PM credentials. The chat room would be set via website (protonmail). This would include options, chat room expiry, users allowed into the room. Once a user logs out of the chat, he/she is not allowed back in and a room must be recreated in order to preserve security. Probably a bad idea, but could be made into something better.

This would be seriously cool!

I would request the ability for each ProtonMail subscriber to give 1–3 of their friends and family a 'friend' subscription to the chat service ONLY. That way I can chat with them instead of using Telegram or, heaven forbid, WhatsApp.

Wickr is pretty good, but slow and closed-source. Telegram needs to enter secret chats for security, so it isn't on by default. CryptoCat is browser only, so no phone app. (Please don't bring up ChatSecure—It's terribly buggy.)

A chat feature would be fantastic. I was just exchanging emails with another Protonmail user and thought how useful a chat client would be.

I thought to myself "here's an idea", but after a quick Google-search this thread turned up.
Yes; IM/chat is vital I think.

I don't agree with the comment that "Route" posted; this has nothing to do with "creating a (yet another) Social platform". We'll definitely do fine as it is without another social network of walls, and posts, and likes, and +1's, and friends, and photos...

But this. A simple ProtonIM-service, well, it just makes sense. Secure, encrypted, safe. Just like ProtonMail. Integrated with the users ProtonMail account where all the chat history is safely and securely stored, with the same level encryption.

As for "Why?", well.... If you can answer the question "why ProtonMail?" in the first place, just apply the same logic and answers to this, and there we go: it just makes sense.

I am not interested in any chat features. I use PM for secure personal correspondence. No need to make another "Social Platform".

Whether the "chat" feature is added onto Protonmail, or created as a separate program by the Protonmail team would be good. Textsecure dropped encryption for MMS/SMS which I'm sure hit some people pretty hard, and the other options for secure "chat" like texting, instant messaging etc are a bit more difficult for most people to use. I would also be glad to pay for such services!

I vote no.

I prefer a true mail service, not an all in, social network mail etc... (like gmail, outlook, yahoo)

See https://protonmail.uservoice.com/forums/284483-feedback/suggestions/7255107-protonchat which has more votes.

Telegram IS NOT secure, read this:
http://security.stackexchange.com/questions/49782/is-telegram-secure

Wouldn't Telegram's secret chats (https://telegram.org/faq#q-how-are-secret-chats-different) cover all the needs mentioned here? Is there a preference to keep chat and email and contacts all tightly integrated under a single trust-umbrella?

Be very careful with this. It could make or break ProtonMail.

I want to apologize ahead for the lengthy comment.

Protonmail team, you will want to keep this feature VERY, VERY SIMPLE and abandon any ideas of making the chat social like Google Hangouts or Facebook Messenger. I recommend OTR and a new handshake every session for PFS.

"Social" media is the scourge of privacy. A person wanting to keep something private between them and another person wouldn't tell their business to the most talkative person in their group. At the most, they would just invite a select few to their group. A chat feature is no different. The Rule of Thirds applies to chats: with more than 3 persons, most individuals lose focus, the subject matter branches off into different tangents, some walk away from the chat and return later, some want to dominate the chat, people that walked away ask "What did I miss?" and someone has to summarize to them, etc... It becomes a mess! Email would better serve that group.

If the following does not complicate the code, chats should have a default self-destruct setting, or the feature should only show x number of lines of the chat and anything beyond that is automatically wiped as the chat progresses (the latter maybe not so much as some people are not very economical with words).

Why self-destruct? There should be absolutely no reason a chat should be saved when an email can serve that purpose.

Things to consider when creating a chat feature:

* No Social Media
* OTR & PFS
* Self-destruct Default
* Rule of Thirds
* Simplicity
* Should do what cannot be answered with "There's email for that." i.e. A chat feature should do what email cannot: instant, real-time, etc...

Please. Albeit I love this kind of idea... PLEASE, not another new protocol.
If you'd really like to make a IM client, contact somebody else with an already successful and open application (like Telegram or Textsecure) and join your efforts

OTR is insufficient. OTR3 describes method for multiple clients, but it's not been done.
Axolotl seems to be better positioned at this point.

I am almost always switching between devices; phone, tablet, laptop, pc, work pc. OTR is unusable when switching between devices, since chat sessions are exclusive to the device you are currently using. History is lost across devices, and you can't just switch (like stand up from your PC, pick your phone, and leave the house).

OTR/End-to-End.

I second this.

I agree with the aforementioned, that some end-to-end encrypted chat (in a mini-window) be available for Pm-to-PM users.

Forget the social, just a simple chat mini-window like gmail had before hangouts. Just something so I can talk to my friends while I am in the email page would be really nice. Keep it simple, it is much better than all crazy social sharing and I don't know what stuff...

Create a Facebook alternative without advertising.

forget social crap, but the chat idea, if encrypted, is phenomenal, I and my friends have been looking for this and no one else offers it.

Instant messaging for proton mail users within the proton mail network that is encrypted by default.