Facebook has apologised to users and blamed "server issues" after WhatsApp went down for more than two hours.

Samsung has shown off the Gear 2, its second attempt at releasing a smartwatch that has mass appeal with consumers.

A prototype smartphone that costs $25 and is designed to appeal to people in developing countries is shown off by Mozilla at the Mobile World Congress.

Chinese electronics giant Huawei unveiled five new products at Mobile World Congress, including what it called the "world's first hybrid smart band".