"Toddlers are noisy. Sometimes peppa pig (on my mobile) is the only thing that will get mine to stay still, and not scream / run around the doctors surgery etc. And I don't carry headphones with me,"
Applesauce - toddlers have always been noisy and active. But saying the only thing that will get your toddler to be quiet and stay still, is Peppa Pig on your phone, is lazy parenting.
Those of us who raised our children before the invention of smart phones/iPads/portable DVD players etc didn't have the option of playing cartoons to keep our children behaving reasonably in public. We parented our children. We taught our children to behave themselves, and we made sure that our children listened to us when we told them to stop.
We didn't always succeed - but we tried. We didn't expect our children to sit silently and stock-still - but we did expect them to behave reasonably well, to stay quiet or quiet-ish, and not to annoy other people. It was hard work for us as parents, but we did it. We didn't abdicate our responsibilities to an electronic device.
If your child does not have special needs or a disability, then there is NO reason why you can't employ good parenting techniques and discipline to get your child to behave acceptably in public, without resorting to your phone.