The iPhone 6 will be released in september but before this release here's what i think is most likely to happen at WWDC in june this year iOS 8 will be released at first and then iPhablet and after that The iPhone 6 will be released in September along with the iWatch this is backed up by KDB Daewoo Securities which have pretty much good record in Apple early leaks.
Apple will sport quad core processor with 4Gb RAM.Apple has made a giant Retina+ IGZO display and the big one with no -HOME button gesture controle will be possible.
Apple will surely add hightech security system Touch ID finger print.
The Retina+ Sharp IGZO display will add feathure in the cap with 4.7 inch Screen it will be awesome to watch movie or play game with 2272x1280p resolution.Apple final deal with GT advanced technologies to produce The Super-tough Saphire Screen in a plant in Arizona . Apple could launch two handset size to compete with Android smart phones. Apple will also introduce the morphing technology this can hide sensors even cameras also .
Rummer is also that iPhone will sport a flexible display with water-proofing technology but less probability Retina sensor will also possible and it will be plus point if iPhone will introduce wireless charging .
Its all about leaks and rummers so wait and watch what will happen in september this year ,All we need is a bigger screen and good battery performance with smooth iOS 8 experience.