Back to the future? Technology trends that struggled
This week the world's biggest mobile phone industry exhibition is happening in Barcelona.
Newsbeat is at Mobile World Congress (MWC) as Samsung, Nokia, HTC and others show off their newest hardware.
But whilst some of the technology on show will end up in your pocket, some of it won't make it that far.
As MWC gets underway, here's a reminder that not everything on show will change the world.
Near Field Communication
Pay for a coffee, check in for a flight or unlock your hotel room door just by tapping your phone on a reader. It sounds simple and convenient.
But despite companies pushing Near Field Communications for several years, they have struggled to convince customers it's the way forward.
EE, Vodafone and Orange have all launched NFC systems in the UK but take-up has been relatively small. Don't ditch your debit card just yet.
LG unveiled the first 3D phone at MWC back in 2011.
No glasses were needed to see three-dimensional images on the phone screen and it could also shoot photos and videos in 3D.
Critics dismissed it as a gimmick and it could be argued they've been proved right.
Just as TV manufacturers and broadcasters have struggled to make 3D a must-have technology for the living room, it's proved unpopular on smartphones too.
The Connected Home
It is possible to turn the lights on, heat up a room or feed the cat using your smartphone or tablet whilst you're out. But not many of us do.
The technology is either too expensive or not practical to install in many homes.
Connected homes can't be written off just yet though.
Google recently bought Nest, the smart thermostat business.
If that company is banking on the concept of smart homes, we'll probably be hearing more about it for sure.
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