A brand new Apple 4.0  iPhone has  been seen in the US, hidden inside an iPhone 3G case.

The device was spotted after an  Apple employee in San Jose left it in a local coffeee shop according to US media sources. The device is believed to have 80GB of memory Vs the 32GB of current models iPhones.

The device was running the new iPhone 4.0 Operating System, before it stopped booting.

The new phone which is tipped for release shortly will have aluminum sides, with buttons for volume in place of the rocker switch. It appears to have a flatter back that's still made of plastic to maintain the necessary cellular reception. The model appears to be a prototype as it uses "X" as a placeholder for both the capacity and identifiers like the FCC ID.

Electronista, said assuming the device is real, it remains possible that the iPhone shown won't be directly reflective of the final model as Apple is known to make design changes even very late into development. However, Apple usually needs to start mass production of iPhones in spring ahead of an early summer launch and thus may have had to produce a small batch for testing.