High-speed wireless technology Long Term Evolution, generally known as 4G is sweeping across the world, with speeds of 20 megabits per second now very common in many countries.

South Korea ranks No. 1 in terms of its LTE speed and coverage according to data collected from OpenSignal, an app that maps cellular coverage. Subscribers to phone networks in South Korea enjoy LTE 97 percent of the time and download speeds of over 25Mbps.

However in terms of speed only, South Korea is not the fastest nation.

New Zealand takes the No. 1 spot as it enjoys 36Mbps.

Other countries ranked top on the list include Japan, Hong Kong, Kuwait and Singapore ― mostly smaller nations as compared to bigger nations like the United States. The assumption is that building a nationwide network is more difficult over a larger area.