In Finland, all kids not only have their own cell phones at age 5 or 6 but also their own home keys. The other day, I had keys made for Luis (10) and Maia (8), although they are not supposed to go out by themselves, without an adult, before they're 12.
But suppose they went just a little bit. Just to take the dog out in the mornings? YES, WE HAVE a DOG now! Her name is Bambina :))) (Some photos of her front side coming soon...) We love her so!