A British synonym of phantom phone, the experience of feeling your phone vibrate in your pocket when in fact it hasn't. You are either imagining it or mistaking other vibration sources for your phone.
Commonly occurs when driving in the narrow cobble-stoned streets of London. More likely to occur if you are talking about someone behind their back. You suddenly think they're calling you, feel an immediate twinge of guilt, followed by immense relief when you realise it was just phone leg.
Ed: "Hang on, my phone's going. Oh no it's not. It's phone leg. I thought it was my daughter. Do you get phone leg?"
Rob: "Yes, but I try not to keep it in my leg."
Ed: "What are you, a terminator?"