The most important thing with 5 pound a month contract phones is the cash back option that you have. You get 120 pounds worth of cash back. With this offer, the effective payout every month will be only 5 pounds making this deal completely worth it if you are looking for a phone that is convenient in terms of functionality.
Usually contracts are for 24 months. This option is available on all the leading networks including Talk Mobile and Life Mobile. Depending upon the network and the offer provided, you can actually get close to 160 pounds as cash back. So make sure you choose your deal wisely.