Some developers seeing new versions of both Apple hardware and software pop up in app usage logs, including the iPhone 6 and the iOS 7 From Techradar:

The new version number for iOS is a little less surprising - the identifier iOS 7 doesn't shock us although hopefully its vastly improved battery management will.

Unfortunately, although it seems Apple is testing the new soft- and hardware already, there are no clues as to what upgrades we can expect to come out of Cupertino.

If past experience is anything to go by, we may get a bit of a look at iOS 7 at WWDC in June 2013.

iPhone 6 and iOS 7 show up in developer logs