Tacendum vs Discrio

Some conversations are just between the people in them. Tacendum is end-to-end encrypted messaging, rooms and calls for iPhone. There is no sign-up: no phone number, no email, no username, no password required. A key created on your phone the first time the app opens is the account. Nobody can look you up unless you choose it — there is no directory and no search. You hand your ID to someone yourself, normally by scanning a code in person; or link an email or a username in Settings, switch on findability, and someone who already knows it can find you. Each is optional and revocable, and none becomes a login. WHAT IT DOES — One-to-one chats, encrypted end to end with the Signal protocol (libsignal). Edit a message, delete it for everyone, reply, react, mention someone by name. Send photos, files, voice notes, or a place you have chosen to share. — Rooms: one conversation for up to twelve people. Only the person who made a room can add or remove anyone, and only they can hand a new arrival the history from before — deliberately, and the room is told when they do. Every room message is encrypted separately for every member; the room's name and everything said in it are hidden from us. — Calls: one-to-one voice and video, end-to-end encrypted, with the set-up riding inside the same encrypted envelope as a message. A room can hold a voice call of up to six people. The first call with someone new is relayed by default, so a stranger does not learn your IP address; one switch keeps every call that way. — Disappearing messages, with a timer you choose per conversation. — Screenshots are disclosed, always. iPhones do not let any app block a screenshot, so instead of pretending, Tacendum tells: take one inside a conversation and the other person is told, in that conversation. No setting turns that off. While the screen is being recorded, mirrored or AirPlayed, conversations are hidden until it stops. — Safety numbers. Every pair of people has one number, and both see the same one. If someone's key changes, Tacendum stops and says so before you send anything else. — App lock: a passcode on top of the phone's own, with an auto-lock delay. One code, two doors — your code opens your conversations, and the same code entered backwards opens a decoy instead: invented people, unreadable messages, while the real ones stay sealed. There is no second secret to remember or to be made to give up. — Blocking and reporting. Blocking is yours alone and invisible to the blocked. Reporting sends us only what you explicitly select, and the report screen says exactly what leaves your phone. WHAT ISN'T THERE No feed. No directory. No ads, no trackers. The app never asks for your contacts — there is no address-book upload. No archive: your history lives on your phone and nowhere else, and undelivered ciphertext clears from our servers within thirty days. And no recovery of messages or keys, by design: the key never leaves your phone, so if you lose the phone, its history is gone. A linked email can win back only which devices are yours and whether you can be found — never a message. We cannot restore the rest — that is the point. WHAT ENCRYPTION DOESN'T COVER Encryption hides what you said, not that you said it. Who each room message goes to is visible to us, and the privacy policy at tacendum.com/privacy says exactly what our servers can still see. We would rather tell you than have you assume. SOURCE Tacendum is free software under the AGPL-3.0 license. The complete Corresponding Source for this exact build is published at github.com/MiranaTechs/Tacendum, tag v1.0-b24. Tacendum requires iOS 15.1 or later. Terms: tacendum.com/terms. Privacy: tacendum.com/privacy. Support: tacendum.com/support or hello@tacendum.com.

No account. No phone number. Nothing to sign up for. Two phones agree to talk by showing each other a code once. After that only those two phones can read what passes between them, and there is no account anywhere to leak, demand, or hand over. NOBODY CAN FIND YOU There is no directory, nowhere to search, and no address that leads to you. You start a conversation by showing someone a code in person, or by sending an invitation link that works once and expires after 24 hours. THE SERVER HAS NOTHING TO GIVE UP Messages pass through a relay holding encrypted blocks — every one exactly 8192 bytes, so size says nothing — under random names tied to no one. No user table, no record of who talks to whom. Blocks are deleted when collected, and expire after 21 days regardless. Tap the byte count under any message and see exactly what the server saw. BUILT TO STAY UNREADABLE X25519 with ML-KEM, the post-quantum standard, and the Double Ratchet, through libsignal — the audited open-source library behind them. Your text is padded to 4096 bytes before encryption, so even the ciphertext length gives nothing away. A message captured today stays unreadable when quantum computers arrive. Compare the sixty safety digits once and you know nobody came between you. If a contact's key ever changes, sending stops until you confirm. FOR THE MOMENT SOMEBODY IS HOLDING YOUR PHONE You choose two passphrases. One opens your conversations. The other opens an app that looks identical, holding ordinary, unremarkable ones. Nothing reveals which you typed: no alarm, no notification, not one second of delay. A third, optional passphrase destroys everything, then opens that same quiet app. Every conversation has a panic hold: press the name at the top and you are on the other side instantly. No button exists to give it away, and coming back needs the passphrase. The app also re-locks on its own — immediately, after a minute, five, an hour, or never. AGAINST THE CAMERA IN THE ROOM Screenshots come out blank. Screen recording and mirroring too. Captures work only where both of you allowed them: your messages sit on the other phone too, so a choice one of you makes alone protects nothing. Allow them and the other person is told the moment you take one. For a second phone pointed at your screen, camera mode opens a message only under your finger. Deniable wording bends the spelling on the way out so a photograph cannot quote you, leaving numbers, times and addresses as typed. Agreed words let one word stand for another, the meaning never reaching the screen. A watermark says which phone a leaked screenshot came from. MESSAGES THAT GO A timer per conversation: gone when you leave it, an hour, a day, a week, a month, or never. Counted from when a message is sent, not read. A ghost message is stronger. Read once, for three to thirty seconds, and then it exists on neither phone. Ghost messages never touch the disk, and a ghost photo can never be captured, whatever either of you allowed. Photos are encrypted on your phone and padded to one of five fixed sizes. NO INTERNET, NO PROBLEM Turn on nearby delivery and a message crosses the room directly — over Wi-Fi, or over the radios if there is none. It works with the internet cut off, and no third party sees the timing, the volume, or that anything was said. WHAT WE WILL NOT PRETEND Any server sees where a connection comes from. We do not log it, but that is a policy, not mathematics: use a VPN or Tor if you need to hide that you use Discrio at all. No software can stop somebody photographing your screen with a second phone. It raises the cost, not the impossibility. Forget your passphrase and your conversations are gone. Nothing is kept from which they could be rebuilt. That is the design, and the one thing that cannot be softened. Notifications say only "New message" — never who, never what — and can be turned off. 17 languages. No accounts, no analytics, no advertising, no third-party code.