Only 33 per cent of mobile handsets in the UK support 4G, suggesting that plans to introduce 5G to London by 2020 may be overly ambitious.

The UK lags considerably behind the US, where 67 per cent of mobiles are capable of supporting 4G. The US, along with South Korea, are the world leaders on 4G adoption, according to a new report by mobile analytics company Netbiscuits.

Looking at smartphone use in Q2 2014, Apples iPhone 5 series has replaced the 4 and 4S as the most-used devices for accessing the mobile web globally, but in the UK the 4 and 4S remain the most popular, with slow adoption rates largely due to long, restrictive contracts and rising sales of tablets.

In China, fast-growing domestic brand Xiaomi has captured traffic share from both Apple and Samsung to gain a 10 per cent share of the Top 100 device traffic for the first time, and there are signs that the device fragmentation trend in Asia is spreading to Europe, leaving marketers with a disrupted landscape in which to reach audiences.