Pandav, an iPhone development company, has noticed that an unreleased iPhone model has been using one of their apps, according to their app’s analytics. The app, iBART, is a public transportation guide for the San Francisco train system, and uses PinchMedia for usage statistics and other analytics. “iPhone 3,1,” an unreleased iPhone model (the current 3GS model is known as iPhone 2,1), showed up in Pandav’s usage logs this month.

Earlier this week, rumors surfaced that AT&T would start selling the iPhone 3G without the standard two-year contract. The purchaser would pay more for the iPhone: $599 for the 8GB and $699 for the 16GB, but would not be required to activate the phone at the store.

MacRumors has found evidence in the newest firmware release from Apple for a next generation iPhone model. The evidence can be found in the file named USBDeviceConfiguration.plist in an unencrypted firmware. Basically, it just references a model that has never been referenced before, model 2,1. Model numbers do not change for storage increases, as all first generation iPhones carried the same model designation, 1,1, as do all 3G iPhones, 1,2.