Channel never reads the phone's address book, and never uploads contacts. A contact exists in Channel because you typed it or paired with it. When you pick a number from the phone's contacts, the picker runs outside the app and hands back one value.
Nothing stops the other person from screenshotting, recording, or photographing what you send them, and Channel would not know. On this phone, two things are shielded from capture, always, with no switch: a view-once picture while it is on screen, and the lock screen's PIN pad. A capture of either is blank. Fields where you type a secret, such as a PIN, a backup passphrase or an AI key, show dots, so a screenshot of them shows dots. Everything else you can screenshot like any other app; it is your phone.
When you leave the app, its card in the app switcher shows a blank garnet page, not your conversations.
Settings › Screen and lock can require the phone's unlock — face, fingerprint or passcode — to open Channel, and again after it has been in the background for a while.
Settings › Screen & lock › Set an app PIN adds a code of your own, 4 to 8 digits. It works even on a phone with no lock at all, and it is asked before anything else — a face alone never opens a PIN-protected Channel. With Require unlock also on, it is PIN first, then face or fingerprint. The PIN is never stored; a slow hash of it is. Three wrong tries start a delay that doubles.
A second code, set under the same heading. Entered instead of your PIN, the lock screen shows one small Confirm. Confirm destroys everything Channel holds on this phone — the key that seals the stores first, then identities, then every file — and the app opens as if freshly installed. Nothing on screen says it happened. Copies elsewhere (a backup, another device) are untouched.
Every store Channel writes is sealed with a key that never leaves this phone's secure hardware. A copied file, a disk image or a stolen backup yields nothing without it.
Nothing else. No analytics, no crash reports, no usage beacons, and Help never contacts anyone.
English is the reference text; any translation is a convenience. Help is stored on this phone and never contacts anyone.