There are many invention which have added to harmony within marriage, the washing machine and modern oven come to mind. For my money though none has made life calmer than the turn by turn GPS on my phone. How did I get to my destination in one piece before I could just put in an address and have a nice female voice tell me where to go. It isn’t looking for street signs that are missing or covered by trees. It doesn’t second guess if you should have gone left at the last light and doesn’t get into a fight when I miss my turn, it just re-calculates how to get there. When it screws up we can blame Apple for a   crappy app. Yep, I am truly blessed to not have to print out maps anymore, and my marriage is better for it as well.