Galaxy S4
Samsung Galaxy S4 concept Expansys

With less than a week until Samsung debuts the Galaxy S4 at its Mobile Unpacked event on March 14 at Radio City Music Hall in New York, rumors about the phone's features keep flying. Several updates and one exciting new rumored spec stand to make Samsung’s upcoming flagship phone even more tantalizing.

The latest development in specs for the Galaxy S4 suggests that its screen will be a literal “green screen” with energy-saving PHOLED material in its AMOLED display.

Android Authority reports the two types of organic light emitting diodes (OLEDs) used to illuminate AMOLED displays are fluorescent and phosphorescent. Fluorescent materials are notably harder to produce and less energy-efficient but tend to last much longer than phosphorescent, so Samsung usually uses a mix of the two in its AMOLED displays -- fluorescent green and blue OLEDs and phosphorescent red OLEDs.

The Galaxy S4 however, is expected to use phosphorescent materials for its yellow and green OLEDs, and fluorescent materials for the blue ones. These "green" PHOLEDs -- phosphorescent materials -- can make the display up to 30 percent more energy-efficient than an LCD panel while maintaining the quality of the display.

The display for the Galaxy S4 is also expected to implement floating touch technology that will allow users to operate the phone by directing their fingers just centimeters above the screen. The end of fingerprint marks is a novel idea to say the least, but the concept is nothing new. It has already been featured in the Sony Xperia Sola smartphone that was inconspicuously released in May 2012. The Samsung Galaxy Note 2 also implements a similar feature, Air View, which allows users to open icons and folders by hovering the tip of the S-pen stylus over them.

The proposed eye-controlled features, Eye Scroll and Eye Pause, that are thought to be powered by Galaxy S4’s rumored front-facing camera may similarly control this floating touch mechanism.

SamMobile also claims to have confirmation that Samsung is focusing on two prototypes for the Galaxy S4, as rumors have suggested. Sources tell the tech website that we should expect one model with the Qualcomm Snapdragon 600 chip and SuperLCD3 display and another with the Exynos Octa 5 chip and Full HD GreenPHOLED / AMOLED display. Rumors indicate that the first will be seen on the U.S. variant while the second will be seen on the international version.

Enthusiasts especially hope to see wireless charging capability on the Galaxy S4. Rumors currently suggest that it will be powered by Qi Wireless Power Consortium.

A recent report from DigiTimes indicates that the Galaxy S4 will in fact include wireless charging capability. The only question that remains is whether the mechanism will be implemented directly into the smartphone or whether users will have to buy separate accessories to enable wireless charging.

Wireless charging seems to be the way of the future, with several mobile brands being a part of the WPC, including Nokia, HTC, LG Electronics, Motorola Mobility and Sony Mobile, sources tell DigiTimes. Nokia, LG and HTC have already added wireless charging capability to their devices. In addition to Samsung, Apple is also expected to follow suit, most likely putting the feature into future iPhones.

Six days is plenty of time for even more fanciful specs to surface for the Galaxy S4. Samsung is already asking "Are You Ready 4?" It's safe to say that every tech enthusiast is answering "yes!"