The UK is considered a leader in many sectors of the technology industry, but it is struggling to join the top ranks when it comes to producing big app publishers.

This, at least, is the suggestion of a new report by App Annie which has ranked the app publishers by their combined worldwide iOS and Google Play revenues.

At the top of the list is the Finnish publisher Supercell, with the UK-based King taking the second place.

From there downwards, however, the UK does not get a single mention in the top 20, nor in the whole of the rest of the 52-strong list.

Japan is the leader with seven entries in the top 20, with the USA following at six entries. China and South Korea follow with three and two entries in the top 20 respectively.

What has King, the UK entry on the list, done right? Founded in 2003 and originally headquarted in Sweden, the publisher is best known for the addictive mobile phone games Candy Crush and Candy Crush Saga.

King’s strong delivery on the economic fundamentals has guided it through the largest ever IPO for a mobile or social gaming company in the US (listing in 2014 on the New York Stock Exchange) and an acquisition in February 2016 by Activision Blizzard.

Candy Crush Saga is free as a download, but the in-app purchases are where the real money is for King. An analysis by the Guardian in February 2015 found that players spent £865m on in-app purchases in 2014.

Players can buy new lives or power-ups to make the levels on the game easier. However the same report found that only 2.3 percent of players of the game pay. A non-gaming alternative might involve offering a basic version of a useful service and then expanding the functionality if the user chooses to pay.

According to a March 2015 App Annie report with IDC surveying over 10,000 people, functionality is the most popular way of monetising a freemium app. This is followed by offering improvements in user experience, such as paying to remove ads.

While King is the only UK entry on this specific list, according to Jens Wikholm, GM of video social network eva, these figures don’t tell the whole story.

What they actually reveal, Wikholm says, is that the UK’s app publishers are finding different revenue generation models to their counterparts.

"The revenue rankings are based on earnings from paid downloads and in-app purchases on the iOS App Store and Google Play Store, but this is not the only resource of income for apps in the UK," says Wikholm.

While Wikholm does accept that British app developers aside from King are "not competing successfully" in the gaming market, he argues that social networks in particular have found alternative monetisation models.

"Apps, like eva, work with external brands to maximise the marketing impact and profile of their product through the use of social media. With a growing number of millennials using social media apps, it is an increasingly important arena where brands can engage with customers."

Paul Swaddle, CEO of independent developer Pocket App, also suggests that the figures are not necessarily an indictment of the UK’s app scene.

Part of this, Swaddle says, is that some of the companies have crucial teams carrying out "the smart stuff in the UK" but the parent company that owns the app is based elsewhere. He cites Sony and Square Enix as examples.

In addition, Swaddle suggests that the enterprise app making scene in the UK remains strong, and is not monetised in the same way.

"Many UK publishers, including our team here at Pocket App, are also heavily involved in enterprise apps, which are used as mobile tools in a professional environment to improve business processes. For example, an enterprise app might be used to track tasks, seamlessly connect to co-workers and local systems from a remote location or complete training courses."

This, again, would not show up as iOS and Google Play revenues.

The UK’s app publishers certainly seem to be pulling their weight regardless. Progressive Policy Institute (PPI) reported in January that over 321,000 jobs in the UK can now be considered part of what it defines as the ‘app economy’.

This was the largest number for any country in the entire EU, according to PPI.

All in all, the verdict seems to be that the UK app publishers aren’t doing badly, but there is room for growth along the lines of international counterparts.