Samsung's upcoming flagship Galaxy S6 smartphone is expected to be announced at this year's Mobile World Congress in Barcelona, while fellow Korean company LG will not be revealing its new G4 as expected.

Mobile World Congress 2015 will be held from March 2nd through the 5th this year and experts are expecting lots of exciting announcements to come from the international conference. 

According to Korean online publication Chosun, Samsung has yet to decide on a final design for the Galaxy S6, but will need to in time for the March 2 announcement and reveal. Right now, the company is debating between a glass back panel and a metal unibody, but one insider says that the metal unibody has been chosen, yet details are still being worked out.

Another sticky detail that the company is struggling to decide on is the use of a dual-edge display as seen in the Note Edge. Some believe that Samsung will be releasing two versions of the S6 -- a normal design and a Note Edge design -- but still others believe that the company won't spread itself too thinly after slumping sales of the Galaxy S5 prompted the company to take a serious look at redefining or streamlining the product line. 

The Galaxy S6 is rumored to have a 64-bit, eight-core processor that is 50% faster than that of the Galaxy S5, which is especially probable considering the fact that Samsung recently dumped the Qualcomm Snapdragon 810 that most other high-end flagships will use this year for its own all-new design.

The screen on the S6 is rumored to be 5.1 inches with a Quad HD Super AMOLED display running at 577 pixel density. The rest of the hardware includes 32/64/128 GB of storage, 4 GB of RAM, a 20-megapixel rear camera, built-in wireless charging, and a whopping 4,000 mAh battery.

Both the Galaxy S2 and the Galaxy S5 were revealed during previous MWC events, so the likelihood of the S6 being shown off this year is very high.

But the LG G4, thought to be the Galaxy S6's biggest competitor in 2015, is said to be missing from this year's MWC event after an LG executive mentioned to Chosun that the company has no plans to release the sequel to the G3 before that.

"We rolled out the G3 in May last year so we do not plan to unveil the G4 at this year's Mobile World Congress and spend more time perfecting the new phone," the LG employee said.

The G4 was expected to feature the same Snapdragon 810 chip that Samsung just rejected on the S6, so there's a possibility that LG is following in Samsung's footsteps by ditching the 810 for something else. This would be devastating news for Qualcomm who has not enjoyed positive press in recent years, but LG (and Samsung) have their own reputations to uphold for releasing top quality products.

While the highly anticipated G4 will not be present, LG will not be missing from the Barcelona event entirely. The company is expected to show off wearables, including the LG G Watch R and others.