The Samsung Galaxy S3 will soon feature lightning-fast speeds as T-Mobile prepares to host the phone on its LTE network.

According to Engadget, the Galaxy S3 was under review with the Federal Communications Commission Monday, probably the final step before the carrier can introduce the phone into its lineup.

The Galaxy S3, dubbed the “Android hero” by CNET  in its best devices of 2012 roundup -- and voted “best phone” and “phone of the year” by several other publications -- has enjoyed an impressive run with more than 40 million handsets sold since its release in May 2012.

But many wonder now if that will be enough to keep the “it-phone of 2012” a heavy hitter in the 2013 market with the  introduction of its successor, the Galaxy S4 looming quite brightly in the horizon.

Samsung Galaxy S3 vs. Samsung Galaxy S4: Sibling Rivalry?

Samsung is expected to unveil the Galaxy S4 at its Unpacked event on March 14 at Radio City Music Hall in New York City, and has a release date projected for April or May, while the T-Mobile's Galaxy S3 with LTE has a rumored release date of March 27, amid all the S4 hullabaloo.

The Galaxy S4’s rumored specs have kept the rumor mills churning as of late, with suggestions of an eight-core Exynos Octa 5 processor or a Qualcomm Snapdragon 600 processor (depending on which country you live in) -- with each clocking in at about 1.9 GHz -- a 4.99-inch 1920 x 1080 Full HD SoLux high-definition display, 2 GB of RAM, a microSD card slot, a 13-megapixel camera, and storage capacities ranging from 16 GB to 64 GB. The Samsung Galaxy S4 will reportedly be powered by the Android 4.2 Jelly Bean mobile operating system.

AnTuTu’s recent benchmark test also determined that the Galaxy S4 will likely support LTE well as GSM and WCDMA with Exynos processor on-board.

Any update for an LTE-enabled Galaxy S3 would likely be just the LTE itself, which Android Authority says has been approved by the FCC under the model-name Samsung SGH-T999L, with readiness for LTE Band 4, LTE Band 17, and support for HSPA+ over the 1900, 1700 and 850MHz bands.

However, that does not make the S3’s specs any less impressive; the top-selling phone features an Exynos 4212 Cortex-A9 processor clocking in at about 1.4 GHz, 4.8-inch 1280 x 720 Full HD Super AMOLED, 2 GB of RAM, a microSD card slot, an 8-megapixel camera, and storage capacities ranging from 16 GB to 64 GB. The Samsung Galaxy S3 was initially powered by Android 4.0 Ice Cream Sandwich and later received Android 4.1 Jelly Bean updates and beyond.

Samsung Galaxy S3: What’s next?

The Galaxy S3 likely won’t be down for the count as yet; with the Galaxy S line’s overall popularity, older devices are still available for retail. The Galaxy S2 can fill be found at T-Mobile, among many other carriers, despite being nearly two years old, a virtual fossil in the gadget world.

Such updates for the Galaxy S3 should allow it to be an oldie-but-goodie for a fair while longer.