Ofcom’s annual Infrastructure Report update shows UK WiFi hotspot usage growing at a faster rate than mobile data.

It says the number of public WiFi hotspots across the UK has more than doubled in the past 12 months from 16,000 to 34,000. At the same time, the amount of data being sent or received by consumers using these hotspots has almost trebled from 750,000 Gigabytes to almost 2 million Gigabytes (2 Petabytes) per month.

Meanwhile, mobile data consumption has increased by 48% from last year, which indicates a slowing of the rate from previous years. There are 84.7 million active mobile data connections in the UK, transferring a total 28.9 million Gigabytes of data per month. That’s the equivalent of 343MB per SIM.

In addition, the number of consumers using a ‘dongle’ to connect their computer to a mobile broadband connection has dropped slightly. It’s currently 4.9 million, having peaked at 5.1 million in 2011.

Other data in the report includes in-building coverage and mobile coverage on major UK roads. It notes that coverage for voice calls on motorways is good, although just 35% of the total length of A and B roads is served by all four 3G networks.

Ed Richards, Ofcom Chief Executive, said “Superfast broadband is rolling out fast across the country, and 4G mobile will reach at least 98% of the population. This is really good news but there remain considerable challenges, not least in hard-to-reach areas for mobile and home internet services. We know consumers increasingly expect superfast speeds, but it’s also important to make sure people can connect over a very wide area. That is why we are doing everything we can to support moves to improve coverage in difficult areas such as roads and train lines.”

[Ofcom Infrastructure Report update; Ofcom coverage maps]