A lost or stolen mobile is bad enough, but things can get considerably worse if whoever picks it up sticks you with a mammoth bill for good measure. Smartphone kill switches or a simple screen lock can save you from such injustice, but hindsight isn't much comfort when your phone's already MIA. That's why all of the UK's major carriers have agreed to a new £100 "liability cap" that could protect you from the worst-case scenario of no phone, huge bill. The "voluntary agreement" -- drafted with government guidance and signed by EE, O2, Three, Vodafone and MVNO Virgin Media -- does come with fine print attached, however. You'll only be eligible for the liability cap, which limits your maximum outlay to £100, if you report your phone lost or stolen to your carrier and the police within 24 hours of it going missing. Contacting your mobile network so they can freeze your account should be top of your to-do list anyway, but is this added level of consumer protection really as awesome as everyone involved would have us believe?