Already got an iPhone you're happy with, but don't want to get locked into a long-term contract? Then make the most of a superb value SIM only deal. Put your SIM card into your iPhone and you're ready to start talking and texting. There are some great value tariffs with SIM only and with 1 month contracts there's no long term commitment. If you spot a better offer or decide to take a new contract deal with a free phone at a later date then you're free to switch with just 30 days notice.