Kuo claims that Apple plans to release not one, but two models of the smartphone: one with a 4.7-inch display and a phablet-sized device with a screen measuring 5.5 inches.
On the first model we will find a Retina display with a resolution of 1,334 x 750 pixels at 326 pixels per inch, while the 5.5-inch device will sport a full HD 1,920 x 1,080-pixel display with a pixel density of 401 ppi.
The design of the new smartphone will also change as it will become much thinner and the bezel on the sides of the display are likely to be reduced by 10-20%.
Both devices will come with 1GB of RAM, an A8 processor, NFC chips, Touch ID and the 5.5-inch version is set to pack a battery that is bigger by 50-70% given the increased consumption of the screen.
In addition, the power/sleep/wake button on the handsets will be moved from the top to the side in order to make one-handed operation easier.
Kuo believes Cupertino will opt for a sapphire crystal instead of Gorilla Glass.
The analyst expects the 4.7-inch iPhone 6 to launch late in Q3 and the phablet model in the fourth quarter.