Samsung Electronics has said that it expects its profits to surge 79% in the second quarter as sales of its smartphones continue to grow.

It has forecast an operating profit of 6.7tn won ($5.9bn; £3.8bn) for the period, its highest quarterly profit since 2008.

Samsung overtook Nokia as the world's biggest maker of mobile phones earlier this year.

Andrew Milroy from technology industry analysts Frost and Sullivan explains what's behind Samsung's recent success.