They say "critical" reforms are needed to provide a better service for customers. Ofcom said its rules meant "virtually all" UK premises would have to receive a 4G signal by the end of the year. The OpenSignal study analysed more than 500m data readings from mobile phones taken from more than 30,000 users between December 1 2016 and February 28 via an app. It ranked 20 of the biggest cities from top to bottom based on their 4G availability.
Top 5
Middlesbrough/Teesside - 82.7%
Sheffield - 79.3%
Sunderland - 79%
Leicester - 78.6%
Leeds/West Yorkshire - 78.2%
Bottom 5
Bournemouth/Poole - 67.5%
Southampton/Portsmouth - 69.6%
Cardiff - 71.8%
Nottingham - 73.3%
London - 73.6%