Samsung launched Sunday a new smart watch, the Gear 2, after a first version won over few critics, adding new features and ditching Google's Android in favour of its own operating system. The South Korean electronics giant revealed the new watch in an unexpected announcement on the eve of the February 24-27 Mobile World Conference in Barcelona, Spain. Samsung is unveiling on Monday its new flagship smartphone, almost certainly the Galaxy S5, and it had been expected to show off the new watch at the same time. Besides an array of features including sports tracking software and a heart rate monitor, the Gear 2 marks an important and widely rumoured step towards independence from Android. The watch, available in two models -- the Gear 2 and the Gear 2 Neo, which has no camera -- will be powered by the Tizen operating system developed  by Samsung with various partners to break free of the Android dominance. Android powered 78.4 percent of smartphones worldwide last year, according to technology consultants Gartner Inc., making it easier for users to switch phones and harder for manufacturers to build customer loyalty. Apple's iOS system accounted for another 15.6 percent of smartphones. The Gear 2, available worldwide from April, has a 1.63-inch screen, a 2.0 megapixel camera that can take high definition video, a heart rate sensor and pedometer, audio that can work with a Bluetooth headphone, remote control for devices such as televisions, and an alert system for incoming text messages and emails. The wrist strap comes in black, orange and brown. The first Gear, launched last September, was criticised by many for being unfashionable and unwieldy. Samsung, like other device makers, is banking on smart devices to boost revenue as sales of smartphones slow in the mature, and most profitable markets. Though smartphone sales surged 42.4 percent to 968 million units last year, according to Gartner, the growth came from developing markets like Latin America, India and China while mature markets such as western Europe and the United States hit the brakes. "We will see all of the handset companies responding to slowing growth in the smartphone market and the difficulty of making money," said Ian Fogg, senior principal analyst of electronics and media at research house IHS. "They are going to launch a number of smart accessory devices including wearable devices that will give them opportunities in new markets to generate revenues and growth." Despite perceived difficulties in selling the first watch to a broad audience, Samsung appeared confident in its latest version. "With the Samsung Gear 2 and Gear 2 Neo, we have enhanced everything consumers love about the Gear to offer unparalleled smart freedom in their everyday life," JK Shin, head of the mobile division at Samsung Electronics, said in a statement. The new watch has been designed to be compatible with a variety of Samsung devices including the Galaxy range of smartphones. The South Korean group sold 300 million smartphones last year, 31 percent of the nearly one billion sold globally and double archrival Apple Inc's 15.6-percent share, according to US technology research house Gartner Inc. The Galaxy S5 is variously rumoured to have a fingerprint scanner on the home button; a 5.24-inch, full high-definition display; a water and dust-proof case, possibly metallic, and a 16 megapixel camera.