Verizon dismissed OpenSignal’s data as “limited and non-scientific”, after a new report said rival T-Mobile US was “within a stone’s throw of matching” the market leader on 4G availability.

OpenSignal’s Q4 State of Mobile Networks: USA report, based on 4.6 billion network measurements for the period, said its testers found a Verizon LTE signal 88.2 per cent of the time. T-Mobile, meanwhile, closed the gap, reaching 86.6 per cent. It also said the companies were neck and neck on overall 4G speed metrics.

Verizon, in a post on Twitter, questioned the validity of OpenSignal’s data.

OpenSignal said in the report its availability metric measures the proportion of time users can access a particular network, rather than tracking geographic coverage.

Verizon said: “OpenSignal provides crowdsourced data. Crowdsourcing favours downtown areas – that’s where the majority of the tests come from – so it doesn’t reflect the depth and breadth of the 2.4 million square miles of our 4G LTE coverage, by far the most in the industry.”

The company continued: “In addition to limited, non-scientific testing, with OpenSignal not getting a signal – the inability to perform a test is not counted against the results.”

Verizon then pointed to other studies from third party testers including RootMetrics, J.D. Power and Nielsen, which it said “do a better job of reflecting the actual customer experience.

“And in those tests, there is no real comparison”. RootMetrics, for example, ranked Verizon top in every category they tested in the first half of 2016, including speed.

Unsurprisingly, T-Mobile’s reaction to OpenSignal’s latest report was more favourable. The company released a statement hailing the results.

“When you combine T-Mobile’s value with great speeds and a coverage map that’s virtually indistinguishable to the big guys, well, let’s just say ‘its on’,” said Neville Ray, the company’s CTO.