All iPhones get a free update to iPhone 3.0, even the original iPhone, but some features are only available on newer hardware including the iPhone 3GS. So, you may be wondering why some features you’ve seen aren’t showing up on your phone. Thankfully, Apple has published a support document titled iPhone: Which iPhone 3.0 software features does my iPhone support? that lists the iPhone OS 3.0 feature and capability differences across iPhone models.