Is your smartphone big enough? Until recently, mobiles were miniature, but an explosion in what we expect from a cellphone is adding a few centimetres to the size of what were once easily pocketable devices. Welcome to the 'phablet', a portmanteau word (combining 'phone' and 'tablet') that describes any handset that has a touchscreen of between 4.6 and 5.5 inches. Fuelled by a desire to watch more videos, play more immersive games and read on a book-sized device, the phablet is so far the reserve of South Korean brand Samsung. Its 5.3-inch Galaxy Note has already sold seven million units, with the market predicted to mushroom to 208 million by 2015. Samsung's Nexus and new S3 both have phablet dimensions, and soon the likes of HTC, LG and Huawei will all follow suit. 'It's the same debate we had a decade ago, but this time it's going away from miniaturisation to bigger screen sizes,' says David Sidebottom of analyst firm Futuresource Consulting. 'Although there does come a point when it's not practical to carry in your pocket.' It's a stark contrast to the miniaturisation fad of 2000-01, when Nokia launched tiny phones that were simple fashion items. 'They were almost too small, but some people loved having such a small handset,' says Sidebottom. 'When people started wanting to do a little bit more with their phones, they got bigger,' he says. 'The new fast networks of 3G and LTE standard have given consumers a range of interactive services that need a larger technology form factor,' says Justin Lello, CEO of Enrich Mobile, pointing to a recent marketing partnership between Samsung and Rovio's Angry Birds game, where new features and levels were available only on a Galaxy Note. ABI Research predicts that the phablet market will increase tenfold in the next 12 months thanks to a new impetus behind the concept of a bigger screen. 'One of the chief drivers for phablets is the amount of time people use their smartphones for web browsing, reading articles and newspapers on the go, or navigating their journeys,' says analyst Joshua Flood. 'The larger screen sizes make a significant difference to the user's experience.' Are phablets just oversized smartphones, or totally new devices? 'People are buying them as their first and primary smartphone, so they shouldn't be considered a separate category,' says Sidebottom. 'Few users will choose a larger 'phablet' over a pocket-sized smartphone,' says Mike Kazarnowicz at Mag+, which produces apps for the Android smartphones and the iPhone, iPad and Kindle Fire. 'A device you can have in your pocket that takes decent photos, can be used to network and listen to music is hard to beat with a larger device.' The simple argument of practicality might stop the phablet from gobbling up the smartphone market, but could 'super smartphones' threaten our increasing affection for tablets? Google's recently announced Nexus tablet has a seven-inch screen, just an inch bigger than Samsung's phablets, but is too big to use for phone calls. Someone with a four-inch phone wanting the Google Nexus - or even the new Kindle Fire, a seven-inch tablet focused on e-books and web browsing - is likely to be happy carrying about both gadgets, but could a mainstream desire for a two-in-one gadget ultimately mean that small tablets are a passing fad? Kazarnowicz doesn't think so. 'Seeing how the average user uses their tablet today, it is a mobile device within the home,' he says. 'They use it for both professional and personal purposes, but most users don't take tablets with them unless it's for a vacation or a work trip, and then it is used as a laptop replacement.' Perhaps the phablet's future lies with consumers not wanting - or being able to afford - two separate devices; it wouldn't be the first unusual form factor to find a niche. 'There's never going to be a 'one-size-fits-all' handset,' says Sidebottom. 'Some people prefer a smaller screen, some don't want a big touchscreen, while others prefer an iPhone size or a bigger screen.' There is a future technology that could really push the phablet phenomenon. Oled (organic light-emitting diode technology) has already appeared - albeit only in prototype forms - in a super-slim, bendable design that can be easily pocketed. 'Until we have foldable, ultra thin screens, phablets won't be able to compete with smartphones,' says Kazarnowicz. For now, Samsung's phablets are selling fast, and there's plenty to play for. The Samsung Galaxy S3 is the official phone of the London 2012 Olympics, and a limited-edition version includes the Visa PayWave NFC contactless payment app. London 2012 VIPs are thus able to pay for items with a simple wave of their phablet, but will their pockets be deep enough?