Rumors and speculations surrounding the next Samsung flagship smartphone, the Galaxy S4, have been around for quite some time now. Several unofficial sources have tried to suggest what the Galaxy S3’s successor will feature and how it will look like. But so far, there has not been any official information from Samsung about the device.

However, with the March 14 release date of the Galaxy S4 just a couple of days away, Samsung seems to let some secrets out.

On Monday, Samsung published an image of a smartphone with the Samsung logo that purportedly showed off part of the real Galaxy S4. Samsung released the image on its Twitter and Facebook pages alongside a message saying: “The countdown for The Next Big Thing has begun. Who’s ready for the Global Unpacked Event March 14?”

One factor, quite evident from the image is that the device looks similar to the Galaxy S3. In addition, it seems that the device does not have speaker for listening to calls.

In addition, Android Central has pointed out that the device in the image also resembles a set of claimed Galaxy S4 images that were posted in a Chinese forum Monday.

However, the leaked device, labeled as the Samsung Galaxy S4 Duos GT-I9502 in the images, was deemed by many as a prototype of the device that could eventually be different from the actual product.

The features and details, revealed by the leaked images, included a 5-inch Full HD AMOLED display, an Exynos Octa 5410 CPU, PowerVR SGX 544MP GPU and 2GB RAM. The device was running on Android 4.2.1 Jelly Bean and it looked like the sides were made of aluminium, while the back was made of plastic.

Shortly after the leak, SamMobile came out with a report claiming that a dual SIM version of the Samsung Galaxy S4 would indeed become a reality.

"Now we do not know if this is the real device but what we do know is there will be a DUAL-SIM version of the Galaxy S IV. SamMobile is able to confirm the Galaxy S IV DUOS, thanks to our insider for the information," said the report, which also cited the forum poster saying that the dual SIM version of the Galaxy S4 would be available only for Chinese network provider Unicom initially.

According to Phandroid, “Samsung teased the Galaxy Nexus in a similar fashion,” revealing “the curvature of the device.” Given that, “it would only make sense if this is really the S4 and not Samsung teasing the S4 by showing us the S3.”

Second Teaser Video Out: Is PHOLED Display Hinted?

Meanwhile, Samsung has released the second teaser video of the Galaxy S4 Monday, in which actor Jeremy Maxwell brings the box home and tries to hide it from others.

When Jeremy opens the box to have a sneak peak at the stuff inside, a glow coming out of the box leaves him stunned. Jeremy says: “It’s my favorite color, it’s unreal… totally amazing.”

With the kid saying the device’s color is his favorite one it can be assumed that the Galaxy S4 will be available in multiple color options, rather than only black and white as previously rumored.

Moreover, since Jeremy is shown quite impressed with the device’s display with the yellowish rays brightening up his face, the possibility of a much improved display also looks plausible. But what kind of improvement will it have?

Rumors are rife that Samsung is going to use PHOLED display technology that will use the colors green and yellow to make the AMOLED display 25 percent more efficient.

According to a report by SamMobile, “Samsung, the biggest OLED user is always busy with the development of new AMOLED/ PHOLED panels. Together with Universal Display, Samsung is able to create next-gen of AMOLED panels. These PHOLED panels are much more efficient and the colors are stunning.”

The likelihood of Samsung teasing PHOLED display in the second Galaxy S4 teaser video is nothing but a guesstimate. However, the very possibility just cannot be ruled out right away.

As explained by Universal Display, “a PHOLED phosphorescent OLED is an OLED that has up to four times higher efficiency than that of a conventional fluorescent OLED… With luminous efficiencies that are up to four times higher than with fluorescent OLED materials, PHOLEDs also reduce heat generation and enhance the number of AMOLED backplane choices.”

Here are some of the key benefits of PHOLED display technology:

- It makes OLEDs well-suited for battery-operated mobile devices, such as smart phones, as well as for large-area TVs and white lighting with less power consumption

- Since electrical energy is converted into heat, rather than light, displays and lights generally experience a temperature rise while operating. PHOLED technology can dramatically reduce this increase

- The lower drive of the PHOLED apparently reduces the power supply requirements of the Thin Film Transistor (TFT) backplane, thus reducing its mobility