Apple Watch 'Killer' to 5G: What to Watch Out for at Mobile World Conference The big event kicks off March 2 in Barcelona.

Mobile World Congress (MWC) in is fast approaching and more than just the latest smartphones are going to be on show.

CNBC runs you through the five biggest themes at the Barcelona event which officially kicks off on March 2.

Samsung under pressure

All eyes will be on the Samsung press conference on Sunday 1 March where the South Korean electronics giant is widely expected to unveil the Galaxy S6.

Samsung's MWC invite hinted at a curved screen as it looks to turn around the company's smartphone fortunes following a tough year.

The once-dominant smartphone player has been recently dethroned as the top handset vendor in both India and China – two of the biggest mobile markets in the world – losing out to high-spec low cost manufactures like Xiaomi. On the premium end of the scale, Samsung's global market share has been eaten away thanks to Apple's large screen iPhone 6 and iPhone 6 Plus.

Analysts have suggested Samsung needs to come out with a product that feels premium and be able to fight back against Samsung.

"They haven't been able to lead the low-end against Xiaomi or high-end against Apple. I'm keen to see how the S6 can change that. It could bring Samsung back if it is really revolutionary," Francisco Jeronimo, research director for European Mobile Devices at IDC, told CNBC by phone.

Apple Watch 'killer'?

It seems like every technology company is releasing some piece of wearable tech or other and this is not expected to slow down at MWC 2015.

While fitness bands have dominated the wearable category, analysts are predicting smartwatches to take center stage at the show as manufacturers look to release a product that can tackle the upcoming Apple Watch.

"I think everybody will be looking for an Apple Watch killer," Neil Mawston, executive director at Strategy Analytics, told CNBC by phone.

LG put out the "luxury" Urbane smartwatch ahead of MWC in a move to draw first blood in the smartwatch wars. But despite the hype around the device category, it is failing to convince consumers.

"People want to buy wearbles but at this point in time there is no user case to put through to consumers," Dominic Sunnebo, strategic insight director at Kantar Worldpanel's ComTech unit, told CNBC by phone.

Asian players

Chinese and India smartphone players made a splash in 2014.

Companies like China's Xiaomi and India's Micromax were behind Samsung's decline and will attempt to stamp their mark on MWC.

CNBC has confirmed that Chinese players Xiaomi, Gionee, Lenovo, ZTE, Huawei and Meizu – a company that Alibaba pumped more than half a billion dollars into – will all be in Barcelona among others.

These companies have made their mark by selling high-spec smartphones at low prices, but analysts are looking to see how low they can go.

"We will see phones with much better specs at much lower prices. But the question is how much cheaper can a smartphone with the latest technology go?" Jeronimo said.

Connected cars

Cars connected to one another and the Internet are destined to be huge in the coming years. The market could be worth $141 Billion by 2020, growing at an annual rate of 32.7 percent, according to Allied Market Research.

So it's no surprise that major automakers and technology companies are jumping on the bandwagon at MWC.

Ford, Audi, BMW are among some of the carmakers with connected technology and experts said the aim is to have vehicles connected to mobile internet. Google and Apple both have in-car operating systems that allow users to carry out functions that they would normally do on their smartphones on the car's screen.

"We expect many connected cars to be showcased throughout Mobile World Congress. We believe Apple and Google will feature prominently thanks to CarPlay and Android Auto," CCS Insight said in a note.

Superfast 5G?

We have just about got 4G mobile internet but major network companies and lawmakers are already talking about the possibility of 5G.

"The path to 5G and the battle for early leadership will be one of the show's hottest topics," CCS Insight's note said.

The European Union and several countries in Asia could be the first to get the technology, with South Korea at the forefront of efforts. The EU has invested 700 million euros ($899 million) over the next seven years and signed a partnership with Seoul last year to develop the infrastructure.

However 5G, which could allow users to download a one-hour high definition film in six seconds, may not be with consumers for a long time yet.

"5G is a bit of hype. Consumers don't even understand the value of 4G," Jeronimo said.