CHANNEL keeps your messages on your device and nowhere else. A backup is a sealed copy that you keep somewhere you choose. Each kind holds only what you can see where you make it, so a file of your contacts is not also a file of your messages.
None of them is required. Make the ones you want, as often as you want.
A contacts, messages or conversation backup holds no keys, no identity, no avatars and no settings. No kind holds disappearing or view-once messages, which were meant to go, or photos, videos and other attachments, which are left out for size.
Every kind is sealed with a passphrase you choose, of at least 8 characters, in the same way as the full backup. We never hold the passphrase and cannot recover it, and without it nobody can open the file, you included.
Plain Text, offered by Export Conversation, is the one exception: plain text is not encrypted, and anyone who opens the file can read the conversation.
You choose where each file goes with the phone's own file picker: Files or iCloud Drive on an iPhone, any folder or Google Drive on Android, a USB drive, an SD card, a computer. Nothing goes to our server. Whoever stores the file learns that a backup exists, its size, and when it was made.
Back Up Everything and automatic backup hold every profile except a profile in Secure Mode that is locked. A locked profile's data goes into no backup, in any form. The result names what was left out: "Backed up. Left out: <profile name> (Secure Mode, locked). Open it to include it." Open the profile, then back up again to include it.
Restoring a backup that lacks a profile says which one first. Profiles already on the device stay as they are.
Keep at least one backup away from this device and away from the place your copies usually sit: a drive at another address, for example. A phone that is lost, broken or erased takes every copy on it with it.
With Secure Mode, CHANNEL is not where your only copy lives: keep encrypted backups of what matters somewhere you choose.
Restore… in Settings › Backup opens every kind. A contacts, messages or conversation backup goes back into the profile it came from, and it adds without replacing: a contact already on this device is left exactly as it is, a conversation already here gains only the messages it lacks, and nothing appears twice. Restoring the same file again adds nothing. The app then closes, and opens on the restored data the next time. When the profile a backup came from is not on this device, the app says so and changes nothing; on a new phone, restore Back Up Everything… first.
A backup can only be restored on the kind of phone it was made on: an iPhone backup onto an iPhone, an Android backup onto an Android.
English is the reference text; any translation is a convenience.
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