My first thought was I wonder if these apps can be used to facilitate voter fraud. It is now easy for them to see which friends are not registered and it is easy in many states for someone else to register you to vote. What keeps them from registering these slacker friends of theirs and then voting in their place? Particularly since so many states are so lax on voter ID. Granted most people won't break the law this way but there are many lunatics on the Left who would take this risk.