Every feature
Everything in the app you install today.
Organised by the six things Vardum protects. Only Vardum marks what none of the ten leading encrypted messengers we compared offer.
Messages
Sealed on your phone, burned when read
Post-quantum encryption
A double ratchet with AES-GCM-256 and hybrid ECDH P-256 plus ML-KEM-768 key agreement, at the start of every chat and again as it continues.
Burn after opening
5 minutes to 24 hours, or off, timed from when the other person opens the message. A background download doesn't start the clock.
Unopened messages expire
A second, separate clock: unread messages expire 12, 24, 36 or 48 hours after sending, so nothing waits on a server forever.
Either side wipes the thread
End this session, from the ••• menu in any chat, hard-deletes the whole conversation from the relay for both people: the messages and the session record, not a hidden copy.
Contacts and groups
Add people by Vardum QR or Vardum ID. Groups of up to 100 use post-quantum sender keys and signed membership, and invites travel inside your encrypted chat with each person.
Photos, video and voice notes
Each file is sealed with its own key, up to 25 MB. When an opened media message burns, its encrypted file is deleted from the relay too.
Safety codes
Compare a short code with your contact once. A pinned contact whose key changes triggers a warning, never a silent update.
Size and timing masked
Fixed-size padding and decoy messages on a jittered schedule, with sender tags that change every step, so the relay sees a uniform stream.
Alerts carry nothing
Lock-screen alerts say only "Notification", or "Incoming call". No sender, no text, no thread.
Files, notes and photos
The rest of your private life, in the same app
Encrypted vaults Only Vardum
AES-GCM-256 file containers with a passphrase-derived key. Everything is encrypted on your phone before upload, and the passphrase never leaves it.
A hidden second volume
An optional second slot inside the same vault, for deniability against a quick look. Resistance to statistical analysis is not claimed.
Notes behind your password
Sealed with a key from your 24 words and locked behind your password, so they survive a full wipe and open again on a new phone.
Steganography Only Vardum
Hide a text message inside an ordinary picture and read it back on any Vardum phone. Everything happens on your device.
Identity
24 words. No name, email or number.
Create in one tap
No form and no address. Vardum makes your Vardum ID and your 24 words on your phone, and signs you in with a hidden login made from the words.
Shown once, never stored
256 random bits from the iPhone's secure generator, turned into 24 BIP39 words. We never see them, and nothing we hold leads back to them.
Your Vardum QR
Every Vardum ID gets its own code. People scan it in the app, or you send it as a picture. Vardum never asks for your phone book.
A fresh start in one tap
Generate a new Vardum ID with new keys and new words, with nothing linking it to the old one.
Move to a new phone
Restore with your 24 words, or move live chats with a one-time encrypted link that expires in about 10 minutes.
The phone itself
For the moment the phone isn't yours any more
Separate decoy and duress passwords Only Vardum
The decoy password opens an empty, working Vardum. The duress password destroys your keys and also deletes your records from the server, then shows the decoy.
A real password lock
Any characters, 4 to 50, with Face ID or Touch ID where you allow it, and a growing lockout after wrong attempts. Vardum locks after 1 minute of inactivity.
You choose where keys live
Sealed on the phone, in the Security chip behind Face ID, or Nothing at rest: never written to storage at all.
Hold until unlock
While Vardum is locked it fetches nothing, so a seized locked phone has no new message data to extract. How it works
Self-destruct countdown
Opt in and Vardum wipes itself from the phone 14 days later, the next time it runs. A warning comes 12 hours before, and you can extend it.
Screen protection
Vardum blurs when it loses focus and blacks out screenshots and recordings. Deterrence, not prevention: a camera pointed at the screen is out of reach.
Privacy controls
One mode. Every dial is yours.
Nothing is pre-set. The guided setup walks you through every control in plain language, with what it does and what it defends against, and your answers become your settings. Change any of them later in Settings.
Messages
Lock and emergency
Keys and always-on
Each control, and what it defends against
Burn after opening
Messages delete themselves this long after the other person reads them.
Defends against: someone picking up or seizing your phone later and scrolling back through what was said.
Hold messages until you unlock
While Vardum is locked, new messages aren't downloaded at all. They wait, encrypted, on the relay.
Defends against: extraction of a seized phone: a locked phone holds no new message data, not even ciphertext.
Nothing at rest
Conversation keys live in memory only and are never written to the phone. Closing Vardum removes access.
Defends against: extraction of keys from the phone's storage. History is switched off automatically, so the two never conflict.
Self-destruct countdown
Everything Vardum keeps on the phone deletes itself on a fixed 14-day clock, the next time Vardum runs after the deadline. Messaging doesn't reset it.
Defends against: confiscation later: once it has fired there's nothing left on the phone to hand over.
Unopened message expiry
Unread messages expire 12 to 48 hours after sending, removed by the relay's two-minute sweep.
Defends against: old unread ciphertext piling up on a server if a phone never comes back for it.
End quiet chats
A conversation with no messages for this long ends and deletes itself, on the relay and on both phones.
Defends against: dormant threads and their keys staying alive for someone to take later.
Timers apply to the chats you start; your contacts' settings apply to the chats they start. The encryption is identical either way. Destructive protections are opt-in, with a confirmation first: nothing ever deletes silently.
Open source
Don't trust us. Read the code.
Vardum's app code is public on GitHub under the AGPL-3.0 licence, so anyone can check the encryption, the 24-word identity and how the server is used.
AGPL-3.0
Anyone who changes Vardum and runs it for others has to publish their changes too.
Every claim labelled
Implemented, new or not claimed, in the public claims register.
$1,000 challenge
100 ciphertexts from the production app, every parameter published except the keys. Try to break one
Vardum's cryptography is self-reviewed. An independent cryptographic audit is planned for early 2027.