iPhone 3G: 3G connectivity iPhone 4: new design architecture/Retina display iPhone 5: LTE iPhone 6: bigger screens iPhone 7: ? So far, I would say the iPhone 4 was the iPhone with the most "surprise features" (not counting the leak). For the others, we knew what was coming. The iPhone 7 rumors are all over the place, so it's kind of nice not to know exactly what to expect! EDIT: It better be a good one, it's the 10th iPhone.