To unlock your iPhone from its carrier, you'll likely need to contact your carrier directly to cancel your contract.

In this guide we’ll show you how to SIM unlock the Galaxy S9 so you can use it on different carrier networks. That way if you bought the Galaxy S9+ from AT&T, you can still take it to T-Mobile if you ...

If you need to find out your iPhone's carrier without a SIM card installed, you can do so through the Settings app.