Help with Hastings Direct YouDrive

I am looking to get the black box YouDrive insurance for my first car as the rates are ridiculous, my mate has it and says that in terms of phone usage you are only penalised if you use it while moving (being stationary with the engine on is fine) on their website and docs I can't find clear detailing of this but their customer service claims that if the engine is on then I can't be touching my phone at all which one is true?