Research by UK media regulator Ofcom reveals that mobile phone signal performance on trains across Britain frequently falls below acceptable standards for basic online activities like social media scrolling or video streaming. Vodafone met "good performance" benchmarks only 17% of the time, Three 21%, and O2 20%, with EE, the highest performer, achieving it 42% of the time. Ofcom identified signal weakness from masts near train lines and signal obstruction within train carriages as primary issues, noting that train Wi-Fi performed well only 1% of the time. Mobile UK cited unique structural and capacity challenges, urging government planning reform, investment, and taxpayer funding for infrastructure to improve these "black spots."