So I made a comparison of going off-contract and staying on contract with two iPhones and 4 GB of data for two years for the new Mobile Share Value Plans from AT&T. It is obvious that you still save money by staying on-contract and paying $200 every two years if you tend to use iPhones and only buy new phones once every two years. But if you buy a cheaper phone like Nexus 5, the off-contract route probably makes more sense. Here are my calculations. Thoughts?