It may seem like the world is already glued to smartphones, but a new report shows we've seen nothing yet. A report released Tuesday from communications company Ericsson predicts that in six years' time, nearly 10 times as much mobile data will be whizzing around the world each year.

Ericsson predicts mobile data from smartphones, tablets and mobile PCs will grow from 5.3 exabytes (5.3 billion gigabytes) to 51 exabytes by 2021. By comparison, the entirety of the Hotmail email service took up just 0.15 exabytes in May 2013. Taken alone, smartphone data is set to increase elevenfold, with each smartphone user consuming 8.5 gigabytes every month by 2021.

Not only will people be using more smartphone data, there are going to be more people using smartphones. By 2021, there will be 3 billion more smartphone subscriptions in the world -- nearly doubling today's figure of 3.4 billion -- to reach 6.4 billion. That year, the U.N. predicts, the world population will be just over 7.8 billion.

The major driver of this growth will be the Asia-Pacific region, which is expected to account for 1.5 billion additional smartphone subscriptions. As soon as next year, Ericsson predicts smartphone subscriptions will overtake basic phones globally.

Those connections are also set to get a lot faster. By 2021, faster WCDMA/HSPA subscriptions are set to account for almost double the subscribers than GSM/EDGE. These fast connections enable more video, audio and photo content to be transmitted, greatly increasing the amount of data transferred globally. Seventy percent of mobile data traffic is predicted to come from video content in 2021, compared to 50 percent today.