What smartphone feature would you like to see in the future? By Matthew Ponsford, for CNN The "Mobile Script" concept phone extendable flexible screen that stiffens when an electric current passes through. Tell your smartphone fantasy in the comments below. The Mobile World Congress starts on 25 February in Barcelona The 65,000 people attending will be hoping to see the brand new smartphones on offer Leave your favorite idea for a new smartphone feature in the comment section below (CNN) -- Each February, the world's mobile technology fanatics wait excitedly to see what will be revealed at the Mobile World Congress in Barcelona -- and this year's event promises to be bigger than ever. As 65,000 people descend on the Fira Gran Via hoping to catch a glimpse of the latest smartphones, boasting everything from quad-core processors to high-definition screens, we're asking readers what features they want to see on the phones of the future. Will 4G connectivity and crystal-clear smartphone cameras revolutionize your world? Or are you holding out for holographic screens and handy "mobile wallet" payments? To see what's on the horizon, check out what industry analysts are predicting in "5 things to watch for at 2013's biggest mobile-tech show" and take a look at our gallery of some of the more far-out ideas that have been imagined already. From the simplest development to the most mind-blowing innovation, we'd like to hear what smartphone feature you want now. Tell us in the comment section below, send us a Vine video or comment on Twitter using the hashtag #cnnfuturemobile February 21, 2013 -- Updated 2113 GMT (0513 HKT) What to look out for at the world's biggest show for mobile technology and arguably the most important show in tech overall. February 21, 2013 -- Updated 1442 GMT (2242 HKT) From a phone that changes color to match your skin tone to one that extends from a watch: These are the wackiest mobile concepts out there. Six big developments that will revolutionize smartphones, including 3D displays and using your phone as your full-time wallet. February 21, 2013 -- Updated 2111 GMT (0511 HKT) With the introduction of 4G expect significant life changes. Faster data speeds will allow us to watch live TV and work and play more easily on the go. February 22, 2013 -- Updated 0027 GMT (0827 HKT) Google finally releases more information about Project Glass, explaining the experience through a series of photos and videos. If new is a necessity, tech is your god and money no object then a $10,000 Vertu smartphone will probably catch your eye. February 29, 2012 -- Updated 1709 GMT (0109 HKT) Mobile devices are being used in radical and innovative ways to modernize healthcare. Find out how here. February 29, 2012 -- Updated 1656 GMT (0056 HKT) Highlights of MWC include a smartphone that turns into a tablet, which then slots into a keyboard, making it a feasible laptop replacement. February 28, 2012 -- Updated 2001 GMT (0401 HKT) The world must act now to prevent a new digital caste system from emerging, Google's executive chairman Eric Schmidt says.