Show Contact Info on the Lock Screen
If your Samsung phone or tablet ends up lost, the lock screen normally gives a stranger no way to reach you. A short contact line - a phone number, email address, or simple message - can sit right on that screen, up to 65 characters long. Anyone who picks up the device sees this text without unlocking it, so think twice before adding sensitive details.
Block a Phone Number
Getting repeated calls or texts from the same unknown or unwanted number is more than annoying when your phone keeps ringing at the wrong moment. Samsung phones let you block specific numbers even if they were never saved as a contact. Once a number is on the block list, calls go straight to rejection and messages never reach your inbox.
Show or Hide Caller ID on Outgoing Calls
Your number pops up on the other person's screen even though you never turned that on, or it stays hidden when you need it visible for work calls. This behavior comes from a network-level default that Samsung phones inherit unless you change it in the phone app. The setting sits separate from Do Not Disturb or blocking and gets missed easily.
Change Contact Name Format
If your contacts list shows names as First Name, Last Name and you would rather see Last Name, First Name, the display setting inside the Contacts app controls that order. This has nothing to do with how a contact was originally saved, so switching the format does not touch any contact data. The change only affects how names appear across Calls and Messages, not the underlying entries or numbers.