Why does my iPhone 4s say 3G not 4 g?

Why does my iPhone 4s say 3G not 4 g?

Your area may not have 4g. Or a setting in your phone is prohibiting it

Because it's not 4G

The iPhone 4s is a 3G phone
there are no 4G iPhones currently
likley the next gen iPhone (likely iPhone 5) will be 4G

Go to setting and change your time & date manually (for example like 1941 march 31st and 6:00) after that try downloading an app and it will fail. Restart the phone and after those steps set up a real time but make sure its right and do not set it manually

Because iPhones are not 4G devices.