Secret codes are great. Whether it's video games or hidden doorways, who doesn't love a good secret code?
Well, your iPhone has some secret dialer codes as well that can help you change settings on your phone. Sometimes they're a little wonky, but most of the time they work and can be super useful!
PLACE ANONYMOUS CALLS using *67 in front off the number you're trying to reach. It will show up as "no caller ID" on the other line. But heads up, lots of people have their phones set up to not accept anonymous calls. If you want all your calls to be anonymous, that's a setting you have to actually fix from the menu by going to settings --> phones --> show my caller ID.
If for whatever reason you do block your caller ID, you can SHOW YOUR CALLER ID one time by dialing *82 before the number you dial.
If you're letting someone borrow your phone and you want to prevent them from making calls, you can BLOCK OUTGOING CALLS by dialing *33* followed by a 4-digit pin you create (e.g. *33*9999#). You'll dial the same code to disable the block.
Pull up a field test to CHECK YOUR SIGNAL STRENGTH by dialing *3001#12345#*. This will pull up a test to check your signal strength for all those times you have full bars but keep dropping calls.
ENABLE OR DISABLE CALL WAITING by dialing *43#. It's already enabled with factory settings, but if you disable it it will send incoming calls straight to voicemail if you're already on the phone.