There has been a flurry of leaks concerning the unconfirmed iPhone 6. Many of these reports suggest that there will be models with two different screen sizes. The most recent leak was posted by Sonny Dickson and shows two models of the smartphone with varied screen sizes; 4.7 and 5.5 inch, respectively.
This leak backs up a previous report that suggested Apple's display supplier, Japan Displays Inc. would be manufacturing a 5.5 inch WQHD (1440x2560) screen that could be used in the unannounced smartphone. It also shows features that were leaked in earlier images, such as the placement of the power button on the right side which is similar to the Samsung Galaxy S5. Even though the back of the devie does not have the Apple logo, it will be engraved like all previous models. As for why these devices don't have the Apple logo, it's likely because they are early production runs to test the assembly process.
All of the leaks that have been coming out have been incredibly similar to each other. Even though these images have yet to be confirmed by Apple, it seems very likely that this could be how the final product will look. We also wouldn't hold our breath that Apple would provide a comment about the leaks seeing that they are trying to crack down on them.
Source and images: Sonny Dickson (Twitter)