Samsung
Show Contact Info on the Lock Screen auf Samsung
Samsung lets you place a short text on the lock screen even when the device is locked. This is meant for situations where the phone or tablet gets lost: a finder can read a phone number or email address without needing to unlock anything.
Where to set it up
Go to Settings ➕ Lock screen ➕ Contact information. Type the text you want to show, then tap Done. The field accepts up to 65 characters, so keep it short: a number and a first name is usually enough.
This is not a full recovery tool. It does not track the device, lock it remotely, or hide personal data behind a password. Anyone who sees the lock screen sees this text, whether they attempt to unlock the phone or not.
If you want stronger protection instead of a visible message, look at Samsung's Find My Mobile options, which can lock, locate, or erase the device remotely. Use the contact info field as a lightweight addition, not a replacement for that.
Turning the feature off works the same way: open the same menu and clear the text field, then tap Done again.