Various rumors regarding the highly-anticipated Samsung Galaxy S4 have begun surfacing of late. The latest rumor, a leaked screenshot, shows a user agent profile of what could be the upcoming AT&T version of Galaxy S4.

The screenshot from the user agent profile of the device mentions the screen specification o 1920 x 1080 pixels resolution as well as the model number that is SGH-I337. The model number of the Galaxy S3 is SGH-I747.

Reports indicate that we can expect the specifications of the AT&T Galaxy S4 to be the same as the international variant, except for LTE support for high-speed Internet access.

In the past, AT&T has offered smartphones in the Galaxy S line-up of handsets, so presumably the Galaxy S4 will also head towards the carrier.

"Unfortunately, there's no particular pattern to follow up on when looking at past AT&T Galaxy S model numbers, in order to see whether the SGH-I337 is indeed the AT&T Galaxy S4. The Captivate (AT&T Galaxy S) is model number SGH-I897. The Galaxy S2 on AT&T has different model numbers as follows: SGH-I777 (Galaxy S2), SGH-I727 (Galaxy S2 Skyrocket) and the Captivate Glide (SGH-I927) while the Galaxy S3 is known as the SGH-I747M," reported Android Authority.

With the success of Galaxy S3 in 2012, Samsung will hope that the Galaxy S4 makes a similar impression in the smartphone space. Speculations suggest that the Galaxy S4 will sport a 4.99-inch Super AMOLED Full HD display. The smartphone is expected to include Exynos 5 Octa (8-Core) CPU, Mali-T658 (8-Core) GPU, and 2GB of RAM.

The Galaxy S4 is expected to be equipped with a 13-megapixel rear-facing camera with 1080p video recording and a 2-megapixel front-facing camera with 720p video. A 2600 mAh battery is expected to fuel the device.

There is no official word from Samsung regarding the release, specifications, or price of the smartphone. We will have to wait for some time before the Korean smartphone maker takes the wraps off the Galaxy S4 and makes it official.