Here's what tech giants are betting on next — from robot dogs to smartphones you can wear on your wrist

The Mobile World Congress, the world's largest mobile show, is a place where device makers show off some of their latest innovations.

And there was quite a lot on display in Barcelona, Spain, this year.

Artificial intelligence took center stage, but there was also plenty of experimentation with different types of screens and first looks at some devices from some of the world's biggest tech firms.

Motorola showed off a concept smartphone that has the ability to bend along the spine-like hinge, including wrapping around your wrist.

The "adaptive display concept" smartphone from the brand, which is owned by China's Lenovo,  has an interface that changes depending on how it bends.

It even has a feature to generate a background to match your outfit.

Lenovo revealed a concept laptop with a transparent screen.

A company representative showed how an object could be placed behind the screen. The laptop's camera can identify it. Artificial intelligence is then used to display information about the object on the screen.

Forget foldables. It's now about rollables, according to one company.

Tecno, a brand under Chinese firm Transsion, showed off the Phantom Ultimate, a phone with an expandable screen.

The screen expands horizontally after it a user presses the button on the top of the device.

The AI Pin from a company called Humane is a small device that attaches to your clothing.

You can ask it questions and it will give you a response.

There's also a camera built in so it can take pictures.

Here's the coolest part: The laser projector beams a menu onto your hand. You can then use hand gestures to navigate.

We posted a video about it on social media here.

Oppo debuted a set of augmented reality glasses it calls the Air Glass 3.

The glasses are