The iPhone 5S and 5C haven't even been announced yet but that isn't stopping Apple from looking to the future. That future reportedly includes larger displays ranging in size from 4.8-inches up to six inches according to "people familiar with the matter" as reported by the Wall Street Journal.
The current iPhone 5 ships with a 4-inch display, the first handset from Apple to include a bump in display size since the release of the original iPhone way back in 2007. An iPhone with a six inch display would put the handset among the largest on the market, rivaled only by phablets like Samsung's Galaxy Mega and perhaps a small handful of international devices.
It's not uncommon for Apple and several other tech firms to test multiple variants of a product before it hits retail. Whether or not Apple would ultimately release devices in multiple sizes remains to be seen but it doesn't seem likely. Unlike Samsung that's content to throw everything at the wall to see what sticks, Apple has up to this point been very calculated with their product releases.
If true, however, such a move would mark a turning point for Apple as they continue to explore options to remain relevant in a red hot smartphone market that's now dominated by Korean rival Samsung. It can be argued that Apple's last truly innovative product was the iPad which singlehandedly spurred the lucrative tablet market we all know today.