Culture secretary Sajid Javid wants mobile networks to share their services to stop mobile calls from losing reception – but communication experts are sceptical
Halfway through our mobile-to-mobile chat, Samuel Johnston goes muffly. Hello? Hello? “Sorry, we’ve just moved into a new office and I haven’t worked out the blackspots yet,” says the head of marketing at OpenSignal.

Complaining about mobile phone “notspots” is the new moaning about the weather, but for those living in the 20% of the UK with patchy coverage it is more than a passing irritant.

Sajid Javid, the culture secretary, wants to eradicate partial notspots by introducing national roaming, allowing users to freely use other networks if their own provider fails to provide a signal.

To some critics, our mobile system looks like the shambles created by under-regulated capitalism. Royal Mail delivers everywhere but mobile providers don’t bother because it’s too expensive to put masts in remote valleys, depriving rural users not just of the basic human right to Facebook on superfast 4G but also the chance to make a mobile call to granny. And it’s not just the countryside: surveys have found notspots in London, Birmingham, Edinburgh, Manchester – virtually everywhere.

Blackspots would be more forgivable if everyone knew their network coverage. Providers offer coverage maps, but when I checked Vodafone’s, it offered an optimistic sketch of its signal in rural Norfolk. Several places (the pub, my mum’s house) where it claimed coverage have none.

“It’s not entirely their own fault,” says Johnston when I ask why providers deceive us about blackspots. “Their testing methods are not effective enough to capture the experience of a user on their network.”

Providers self-report to Ofcom, so there’s little independent data on coverage but this blackspot black hole is being filled by companies such as OpenSignal, which produce coverage maps crowdsourced via an app.
Johnston is critical of the national roaming idea. “It’s another example of government making decisions without supporting data,” he says. By looking at “time on no signal” v “time on emergency calls only” (a sign that a phone can potentially access rival networks), OpenSignal calculates that, even in London, national roaming would not eradicate notspots but only cut time spent with no signal by 25%.

James Barford, an independent mobile analyst for Enders Analysis, also argues that national roaming is a bad idea: if payments that providers will have to make to each other are too low, there will be no incentive to build better coverage; too high and “cheap and cheerful” providers will be put out of business. Better, he says, to loosen planning rules to allow for higher masts.

It may be tempting to fantasise about nationalising the network, but Johnston judges that “absolutely impossible” and Barford says it would eradicate innovation. Worse, a perfect national mobile signal would eliminate peace in remote valleys, render redundant a perpetually useful excuse for avoiding calls and mean the end of the “no signal” dramatic device that allows thrillers to stagger on in the era of not-quite ubiquitous mobile communications.(from the guardian.com)