Why iPhone's all have IOS 6 software
Any iPhone lower than 4 will have io6 . But if you just bought one , if might not have been updated , usually they make a lot of phones before the ios 7 , so you might have bought an older ons
they are all ios 7. and its because thats their software they are currently using
iPhones have whatever IOS version has been installed.Some have IOS 6, some IOS 7 and older iPhones have prior versions.There is no ALL condition when it comes to iPhones.
Any iPhone released after the 3GS can have iOS 7. Anything below that can have iOS 6 or lower.