shows the profit margins
Basically mobile contracts work like this.
you pay per month * 18 months
they get this say you pay 30/month = 540 + £99 for 8GB phone = £639
this means that this £639 needs to pay for
Cost of phone from Apple
Cost of O2 Equipment (mobile masts data usage etc, costs to other networks in call fees)
Cash to seller for selling phone (in case of WEB it goes to profit)
Cost of unlimited data
Guaranteed profit
Remember that when you call someone else on another network it costs O2 to connect the call, so on a cheap tarrif like £30 after all other costs there wont be much left to pay the other networks in connect calls costs. thats why higher tarrifs have more minutes because O2 can afford to pay to connect the calls. Also remember that the line Guaranteed profit comes before anything else for O2.!!