Quidco on carphone warehouse is £20 for the iphone, it has its own catagory on quidco now.
O2 and Apple are the only other outlets selling this, you may possibly be able to get £23.33 or £35 quidco on O2 website but im not sure, hopefully someone can confirm this.
At some point there will be a £23 off apple code which would make it £246 - 3% quidco = £238.62
Order from Apple Store, using £23 off code: CPUU3SLGLH
quidco is: £6.27
So total after discount code and quidco is officially: £239.23
So its a crisp £30 cheaper than standard iphone deal