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It may be one of the world's most important cities, a global financial hub and culture capital, but there's one thing London just can't get right: mobile phone signal.
The capital ranks 13th in a list of 16 cities in the UK, paling in comparison to rivals like Manchester, Birmingham and Liverpool.
The survey, by RootMetrics, tests the speed and reliability of phone calls, texts and mobile internet, giving each city a score out of 100.
Here are the worst performing major cities in the UK (score out of 100 in brackets):
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