You can use regular telegram chats for every day everything. It's encrypted and nothing wrong with it. If you are implying it is not encrypted - it is.
In the settings, there is a value you can set and a time-out figure will be attached to all the chats you start, between 1 day and 1 year. I usually set mine to 1 week. If conversation becomes sensitive, depending on how sensitive, I either downgrade to 1 day or switch to Secret Chat for most security.
Non-Secret chat is fine for every day traffic, and users should encrypt all their traffic so the Alphabets have no idea what is important and what is not. Telegram does that. There are no special hoops to jump through. It's organic and pretty simple. And looks like a text messenger.
The reason the Secret Chat is not turned on by default is because Telegram is replicated to all the devices you are logged in. You can have x number of computers and tablets. A conversation you start on your phone will be replicated to your tablet(s). So if I see something on the phone, or desktop, like a cool place to eat, throw it in the "Saved messages" folder, then the tablet stored in the car will show that and all the other devices. A general chat like that is for low-priority low-security messages. It's not that the message is unencrypted, they don't have to break it, they just have to steal one of your computers/tablets/phones to get access to all the messages, and for high priority mesg short time outs are a must anyway. Say one day and there is nothing beyond 1 day that's shown.
Not offering the best security possible is "broken by design" to me.
It is a trade-off per user request. It's self-evidently not safe as if one your devices gets stolen, they will be able to read your messages. You can login to your master account and terminate all other login sessions. You trade security for convenience. If you want most security, you can trade convenience for security, Secret Chats are not replicated to your desktop or any other devices.
While I'm ranting around Neither Signal Whatsapp or Telegram set a message deletion timer by default.
They all do. For the chats you start, all 3 can be set to a default timeout value. whatsapp is kind of limited, it's either 1 day or 1 week or 90 days. Telegram is most flexible, it ranges from 1 day to 365 days. Signal ranges from 4 weeks, 1 week, 1 day, 8 hours, 1 hour, 5 minutes, 30 seconds and then there is the custom time for most granularity not to exceed 4 weeks. Viber does it too, up to 1 day.
To reiterate, you only need a phone once for telegram and you can buy a burner or use someone's else number, you don't need it past that point unlike whatsapp and Signal and Viber.
Another really neat feature of Telegram I haven't really seen elsewhere (Well Signal started doing it recently, apparently inspired by Telegram). You can set a message into the future. Say a week or a month from today. So the message will be sent if something does not happen, versus something happening. Say you do some risky international travel, and you can ping a mesg 2 weeks into the future with instructions how to proceed if your plane does not land, etc. etc. Very neat.
The cool thing about Signal is that it's uber paranoid, has a lot of security checks that it does. It also has more granular timeout settings, down to seconds and minutes and hours. I frequently donate to them.
The only thing I find mildly irritating is that the history of timeouts is not deleted, so if you carry a conversation, initially set to 4 weeks timeouts, then jump to 1 day, then to 2 hours, a person scanning your phone, even with all the messages are deleted, will deduce something important went down when you went from 4 weeks to 2 hours back to 1 week or such. There is no reason to keep the timeout or call history around. I want the whole thing wiped clean, like Wickr. They put even more paranoidal thought into their security features.
Signal too has the general sandbox type "saved messages" folder which is blasted across devices, and you can set a timer on it as well. And it's encrypted.
I think the biggest issue is someone hacking the computer, or placing malware or stealing the phone or something versus actually breaking one of these messengers. There is a a weak link and it's not Signal/Telegram itself.
There is the wire messenger. No phone needed. No other advantages over signal/telegram.
As a bonus there is also the Viber messenger, popular in Eastern Europe, it's more popular than signal world-wide. It has some interesting features. I don't know how secure it is, they claim messages are encrypted. It disables screenshots if the timeout is set. Its timeout settings are kind of weird, 10 seconds, 1 minute, 1 hour and 1 day. I wish they had a week also. But you can replicate the session to the desktop.
I almost forgot. The real power of telegram is that it is an entire ecosystem. You can easily spin up a channel or a group of up to 200,000 followers. And post media, all with the timeouts set. They put a lot of work into it. It's a messenger with social media built in, which is much nicer implemented IMO than Instagram/FB or anything else. It just works.
Signal too does groups.
So does whatsapp. So does viber. I would trust telegram/signal over whatsapp/viber.
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you can setup your own matrix server (to much hassle).
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