AT&T’s CEO¬†Randall Stephenson told investors yesterday that with smartphone penetration approaching 90 percent, the existing business model – where carriers sell highly-subsidized smartphones to drive demand – will have to change.

When you’re growing the business initially, you have to do aggressive device subsidies to get people on the network. But as you approach 90 percent penetration, you move into maintenance mode. That means more device upgrades. And the model has to change. You can’t afford to subsidize devices like that.

Many U.S. iPhone buyers don’t realise the true cost of their handsets, as carrier subsidies mean they typically pay no more than $200. The full retail cost of those handsets, however, ranges from $549 for a 16GB iPhone 5c to $849 for a 64GB iPhone 5s. The balance is paid by the carrier, then clawed back through the contract payments …¬† expand full story