RootMetrics said Manchester came first for mobile performance in a ranking of the 16 most populous urban areas in the UK, with London only achieving 13th position after dropping four places from previous tests.
The findings are based on data gathered in the second half of 2015 and compared to tests in the first half of last year. The mobile analytics company said Manchester replaced Liverpool at the top of the table compared to previous tests, with Birmingham remaining consistent in second position.
RootMetrics' overall performance rankings are a result of nearly 400,000 test samples and more than 12,000 miles driven across the UK. Overall performance scores are a combination of reliability and speed results from data, call, and text testing.
The company calculates an average score for performances observed on the EE, O2, Three and Vodafone networks in the 16 most populous urban zones, and weighted these scores according to the estimated number of subscribers for each operator.
The ranking also once again highlights London's struggling performance, despite it being the most populous and business-critical city in the UK.
"Startlingly, London finished 2015 ranking no higher than #10 in any category including reliability, speed, data, call and text," RootMetrics said. Manchester was in first position for data performance and network reliability, while Liverpool still came out on top for network speed.
Scott Stonham, RootMetrics general manager of Europe, said: "Providing good mobile coverage in London is always going to be difficult due to the density of the population, the architecture and changes in demand on capacity. Our data shows there is still some room for improvement in some of the UK's most populous areas, and more needs to be done to ensure a good mobile service -- a vital part of a city's basic infrastructure."
Bristol, Cardiff and Hull received the lowest weighted average mobile performance scores, and the bottom three ranking positions were unchanged from the first half of 2015.
- see this RootMetrics report
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