Not sure what you mean with life changing, but from experience: if you ever find yourself in a situation where you go on a trip and your health might depend on the ability to call or navigate, don't ever use a smartphone for that ability :)
Also got to do a lot of deep thinking while traveling across Europe. Wish they were more united. There are so many unbelievably talented people in Europe. It would be interesting if they could compete head on with the US and help to keep us more on our toes sort of like a second super power. I think that would be good for the world. Alas I saw how things like this are just not possible because people do not believe in it. The same problem I had before I came to Europe! Its unfortunate because Europe has all the components to be just as competitive as the US (in my opinion). :)