Navigation with Maps

Actually something like this would probably be better, but I still need to test it.

distance:(n, dp) => {
        if (dp === undefined) {
            var miles = n / 1609.34;
            dp = miles < 10 ? 1 : 0;
        }
        return n < 152.4 ? round(n * 3.28084) + "ft" : round(n / 1609.34, dp) + "mi";
    },