Internet penetration will cover 44% of the world population by the end of 2015, according to a UN report based on present data and trends.

The eight-fold increase in 15 years will see a total of 3.2 billion people accessing the internet, says the International Telecommunication Union report.

However, there are still four billion people in the developing world without access to it; among the least developed nations, only 15% use the internet.

The steep rise from 400 million users in 2000 is a measure of the technological progress, says the report that tracks the United Nations' Millennium Development Goals.

"These new figures not only show the rapid technological progress made to date, but also help us identify those being left behind in the fast-evolving digital economy, as well as the areas where ICT investment is needed most," said Houlin Zhao, secretary-general of the International Telecommunication Union, said at a press conference in Geneva, Switzerland.

Reaching remote, inaccessible areas and expanding the spread of the internet could soon be possible with a host of new innovations in the pipeline. Among them is Google's Project Loon, which plans to send a fleet of internet-beaming balloons into the sky.

The balloons can float for more than one hundred days as they cross the globe and beam the internet down to those who are not yet online.

Facebook has completed its first test of a solar-powered drone that could could fly at altitudes of more than 60,000ft for a number of months and provide connectivity to most remote parts.

The number of internet users worldwide will surpass three billion in 2015, according to figures from eMarketer, with more than two out of five people having access. Mobile broadband connections are driving internet access and usage in most countries.

By 2016, it predicts India will have the second largest internet user population. At present the third largest online user base after China and the US, users in India alone were over 300 million by end of 2014, while the mobile internet user base, which is growing exponentially, is expected to cross 200 million in 2015.

A Ericsson survey found 36% of people are increasingly using mobile broadband for banking services, bill payments and e-commerce besides accessing social networks, downloading music and videos, browsing and sending emails.

However, issues of inconsistent speeds and app usage outdoors, and long webpage load times indoors, are major challenges.