According to a recent study by GSMA, 65% of UK-connected app users are on Apple's iOS.
Coming in second is the Android OS by Google, at 31% of UK's population. Symbian came in third at just 1%, with a mixture of other OS' at 3% of the total.
The total number of app users on smartphones stands at 8,753,197 unique users.
In addition, when it came to apps that were accessed, Google reigned, owning three out of the five top ranked apps. Google Maps was the most accessed app with 6.4 million unique users.
"We are excited to release the first public census-level data from the GSMA and comScore on mobile application usage," said Henry Stevens, media director, GSMA.
"Apps have become an important entry point for accessing content on mobile devices and their usage will only increase with the rapid proliferation of smartphones. We look forward to delivering to the UK market these critical insights to help understand the mobile ecosystem." he added.
In April 2011, 40% of the 21.8 million UK mobile internet users accessed a connected application. Google Maps reaches 73.3 per cent of all UK app users. Yahoo's Weather app ranked second with 3.6 million followed by Facebook's app with 3.5 million unique visitors. Another two apps published by Google - Google Mobile and YouTube - rounded out the top five.
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