It's the week that Europe's tech geeks and mobile nuts live for. And this year's Mobile World Congress (MWC) proved no disappointment with the likes of Samsung to Xiaomi making a splash with a range of new products.

A surprise entrance from Facebook boss Mark Zuckerberg at Samsung's press conference on Sunday and the massive amount of virtual reality (VR) experiences at Europe's biggest consumer electronics show were among the highlights of the events.

CNBC runs you through this week's devices and don't-miss announcements.

Samsung took the wraps of its flagship Galaxy S7 and S7 Edge, the next version of its curved screen smartphone.

Some of the new features from its previous S6 Plus include a bigger battery life and an "always-on display" where part of the screen remains constantly on with an app, such as a clock, but on a low power level.

The S7 Edge has an improved edge functionality, including a feature called "Task Edge" which allows you to bookmark specific tasks to be carried out quickly, such as immediately accessing the selfie camera or going straight to the message thread of a specific contact.

As growth of the smartphone market slows, Samsung and other device makers are looking for new product categories. The South Korean electronics giant is betting big on virtual reality and released the Gear 360, a camera which can film in 360 degrees.

The images can be stitched together on a Samsung device and viewed through the company's $99 Gear VR headset.

Perhaps the biggest surprise of MWC was Mark Zuckerberg turning up at Samsung's press conference on Sunday.

The Facebook boss spoke about the partnership between Samsung and Facebook. The social network of course owns VR company Oculus whose software is in Samsung's Gear VR headset.

In a challenge to the likes of Apple and Samsung, Huawei launched its first 2-in-1 tablet with detachable keyboard.

It comes as the Chinese network infrastructure and device maker has seen strong growth in its smartphone division, and is hoping to replicate that success with the MateBook.

Xiaomi unveiled its latest flagship smartphone, the Mi5, during the show -- the company's first European launch for a handset.

But the Mi5 is not actually available in Europe with the press event being a bid to drum up support for the brand outside of China, India and Brazil where it currently operates.

"We primarily focus on existing markets…we're beginning to work our way into other markets," Hugo Barra, vice president of international at Xiaomi, told CNBC in a TV interview on Wednesday.

Taiwan's HTC took the wraps off the HTC Vive virtual reality headset at MWC, pricing it at $799 and making it available for pre-order from Monday.

It's the closest competitor to the Facebook-owned Oculus Rift and highlights how device makers are seeing virtual reality as the next big thing.

The LG Rolling Bot is a small soccer ball-sized device that can be controlled via a smartphone and roam around the house. It has a camera built in which can be used for surveillance when you are away from the property. It also allows a user to control anything in the house using infrared such as the TV.

Sony showed off a number of concept products including the Xperia Projector, a portable short-throw projector that turns anything into an interactive surface.

A user can place the device next to a table for instance, and can play around and interact with the projection that is shown.

Amid the generic rectangular smartphones at MWC, the RoboHan device stood out among the crowd.

It's a robot-shaped phone with a camera and built-in projector. It can also walk around.

Hewlett Packard made a big play for the business market when it unveiled the 5.9-inch Elite x3 phablet.

The device runs Windows 10 and users can put the device into a dock and connect it to another screen to continue working away from their desktop. The dock allows a user to add a keyboard and mouse.

The SPro Plus is a "smart projector" with an 8.4 inch display. It runs Android allowing users to download apps from the Google Play store and project that onto any surface.

It's also small enough to be portable.

LG took a slightly different approach to smartphones this year, making their latest flagship model – the G5 – "modular", meaning people can remove and replace certain aspects of the phone.

The South Korean electronics firm showed off accessories such as a Bang & Olufson amplifier to clip into the device, and the Cam Plus, another add-on device that gives your phone functionality similar to a traditional camera. It has a wheel to scroll and a shutter button to take a snap.

Another one of Sony's big concept products is the Xperia Agent, a device similar to Amazon's Echo, which sits in the home and controls several devices.

Users will be able to speak to it so it can carry out tasks such as playing music or retrieving information.

Sony is hoping to capture the emerging "smart home" trend, but it did not give a potential release date as it is still a prototype.

The Orange Rise 31 is a 3G device with a 3 megapixel camera, 4 inch screen and runs Android. The $40 handset comes with a bundle of text messages, 500 megabytes of data per month and minutes, for an average of 3 months. After that, users will have to top up.

It's aimed at the Middle East and Africa.

The Xperia Ear is small single earbud that people can wear and can get updates, such as the weather or an alert, from your smartphone.

Users can talk to the device and it can carry out tasks like replying to a message or giving you directions.

The Xperia Ear is set to launch in the summer but has no price yet.

Alcatel's Idol 4 is a smartphone and virtual reality headset in one…sort of.

It's the company's latest phablet device and the packaging for the phone can be folded to become a virtual reality headset.

A key feature is the customizable "Boom button" which can carry out a command you've assign it.

Sony released a new line of smartphones - the lower priced Xperia XA, the mid-range Xperia X and the top-end Xperia X Performance.

All of them boast 5 inch screens and come in a variety of colors. Sony touted the 23 megapixel main camera and 13 megapixel selfie camera.

Users can track a moving object and the camera will lock onto it, keep it focused and take a number of snaps in order to keep the image sharp. Sony also said its camera is twice as fast as the one on its previous phone, the Xperia Z5.

The LG 360 Cam is a handheld camera that allows people to take 360 degree video, while the 360 Viewer is a virtual reality (VR) headset that looks like glasses.

Garmin released its latest wearable – the Vivoactive HR – which is a cross between a smartwatch and fitness tracker.

It allows people to track fitness metrics as well as messages and phone calls.

The Vivoactive HR has GPS capabilities and comes installed with a number of fitness apps, including the ability to track new activities such as rowing and skiing, which were not available on the previous version of the device.