Private content.
Clear boundaries.

Development preview. i247 is not independently audited and does not implement forward secrecy. Do not rely on this preview for sensitive or high-risk conversations.

What is encrypted

Text, photos, and videos are encrypted on the sender’s device using libsodium authenticated public-key encryption before upload. The server stores ciphertext. The intended recipient’s device decrypts it. Private encryption and signing keys are generated on your device and stored in a passphrase-encrypted local vault.

Verify who you are talking to

Compare the conversation safety code through a trusted channel or in person. Keys are pinned when you add a contact; a later change stops the conversation until investigated. An unverified first contact depends on the service returning the right public key.

What the service can see

Usernames, public keys, contact relationships, sender and recipient, message timing, encrypted file sizes, and request/network metadata are not hidden by content encryption. The hosting provider processes network traffic and access records.

No location-sharing feature

i247 does not request location access, upload your address book, or offer maps and live location. Images are redrawn before encryption to remove original photo metadata. Uploaded videos may still contain embedded metadata; the app warns you before sending. Text and visible details in photos or videos can reveal places.

Your username and your device

A username is a unique account handle, between 3 and 24 letters, digits, or underscores. Names are case-insensitive. Unique usernames do not establish a person’s identity or prevent someone from creating multiple accounts.

Your passphrase unlocks the keys stored in this browser or installed web app. It is not sent to the service. Export an encrypted backup and keep its passphrase safe. Clearing browser data, losing your device, or losing your passphrase can make your account and history inaccessible. There is no email or phone-based recovery.

Limits of this version

This version supports one-to-one text, photos, and videos up to 6 MiB before encryption. It does not offer calls, group chats, or background push notifications. New messages refresh while the app is open. Native Android and iOS releases are not yet signed or distributed.

Long-term encryption keys are used without a ratchet, so a compromised key can expose earlier messages. End-to-end encryption also cannot protect an unlocked or compromised device, a malicious future client update, screenshots, or copies kept by the recipient.

Screenshots and recording

The website and installed web app cannot reliably block device screenshots or screen recording. When the browser reports that i247 has gone into the background, a black privacy cover hides the interface and pauses videos. You must tap Return to conversation to reveal it again. This is a best-effort background cover, not capture prevention; operating-system app previews may be taken before the browser sends that event. Message timers continue while the screen is covered.

Capture protections in the native Android and iOS source are not active in the website or installed web app. Native releases still require signing, device testing, and distribution. No version can prevent someone photographing a screen with another device.

50 seconds after opening

Incoming text, photos, and videos stay behind an Open button. Unopened items remain available. When the recipient taps Open and the server acknowledges it, one continuous 50-second timer starts. Reopening, reloading, or closing the app does not restart that timer. The timer applies separately to each message, photo, or video.

At expiry, the app removes the content and the API stops returning it. Other connected devices synchronize the expiry; an offline sender cannot learn of a new opening until reconnecting. Physical removal of encrypted files happens during subsequent authenticated service activity and retries if storage is unavailable. This is not a guarantee of instant erasure from every device, storage system, or provider backup. Screenshots, recordings, and copies saved by recipients cannot be revoked.

Storage and account controls

The service records opening and expiry timestamps to enforce the timer. Minimal message identifiers may remain to prevent an expired message being uploaded again under the same identifier. Blocking a username stops new messages. Self-service account deletion is not implemented in this preview.

Cost and separation

i247 has no app fee or payment flow. Its public hosting address is free, but hosting usage remains subject to the providers’ plan limits and terms. Unlimited free operation is not guaranteed. This messenger has its own application, accounts, database, and encrypted-file storage. Provider accounts and hosting quotas may be shared with other projects.

Cryptography reference

The encryption primitives come from libsodium’s authenticated encryption API. Using a cryptographic library is not a security audit of this app or its protocol.