Apple is allegedly working on a significantly larger iPhone. The current top model, the 5S, has a screen diagonal of 4-inch, but like the 12.9-inch iPad, to debut in October of 2014, the next phone might be quite a bit bigger.
It's still unknown whether the phone will exist on the side, similar to the current iPhone 5C, or that the device is actually the iPhone 6. Rumour has it that the phone might make a debut as early as May of 2014. Internally, it should be quite a step forward compared to the current devices. The iPhone 5S features an Apple A7 core, a 28 nm produced by Samsung. The next iteration is said to be based on a 20 nm SoC.