After Galaxy S3 made waves in 2012, Android fans are waiting for the launch of the Galaxy S4. However, the successor of the best selling smartphone of 2012 is not expected to be unveiled until the second quarter of 2013.

The reason, according to Taiwanese news outlet, DigiTimes, is a delay in producing a 441ppi display.

DigiTimes quoted a source as saying that the 4.99-inch AMOLED panel, which Samsung Display (SD) wants for the device is proving difficult to make due to issues with its evaporation process technology.

"SD is reportedly seeking more advanced LITI technology from 3M that will enable OLED materials to be printed on glass more smoothly," reported the Web site. "However, the sources added that SD is still having issues with that technology, particularly with blue-colored materials, causing delays in the mass production stage."

The delay means that it's unlikely that the Galaxy S4 will be unveiled at the CES 2013 in January, but should be expected instead at Mobile World Congress 2013 towards the end of February.

One of the reasons why Samsung is paying so much attention to the display is the new bar set by the 1080p display on the HTC Droid DNA smartphone.

Also known as the J Butterfly, the HTC device arrives with a 5-inch panel supporting a resolution of 1080 x 1920 and a pixel density of 440 ppi, which has left manufacturers playing catch-up with the Taiwanese company.

Other rumors are already circulating as to what Samsung's final device will look like, with some speculating a mammoth eight processors.

EETimes says that instead of packing a quad-core processor with a fifth core tasked with minor background processes, Samsung plans to sandwich two quad-core chips into one offering. - four Cortex-A7 1.2GHz cores and four Cortex-A15 1.8GHz cores.

GSM Arena also believes that the Galaxy S4 will sport a 13-megapixel rear-facing camera, and Samsung is reportedly readying a new line of flexible LCD display panels for 2013, which could be included in the smartphone.

These screens are cureently among the most innovative developments in smartphone technology, using breakthrough OLEDs that are so thin that they can be put on flexible material such as plastic or metal foil rather than the glass used on traditional display panels. However, Samsung has refused to be drawn on any of these rumors so it is all speculation at this point.

The Galaxy S2 and Galaxy S3 smartphones were released around May and many expect the Galaxy S4 to have a similar launch date.