It's not just storage and screen size that differentiates between the different iPhone 7 models. There are also significant performance differences between the different models. Tests suggest that the cheaper 32-gigabyte versions have significantly poorer performance than their more expensive counterparts, and that some also display significantly poorer 4G performance. Differences between iPhone 7 models differ quite significantly!
I love technology and how it enhances our lives! Just think, without the Apollo moon missions, we might not have calculators! Imagine!!