How to create a link for all mobile devices that opens google maps with a route starting at the current location, destinating a given place?

I haven't worked much with phones, so I dont't know if this would work. But just from a html/javascript point of view, you could just open a different url depending on what the user's device is?

<a style="cursor: pointer;" onclick="myNavFunc()">Take me there!</a>

function myNavFunc(){
    // If it's an iPhone..
    if( (navigator.platform.indexOf("iPhone") != -1) 
        || (navigator.platform.indexOf("iPod") != -1)
        || (navigator.platform.indexOf("iPad") != -1))
         window.open("maps://www.google.com/maps/dir/?api=1&travelmode=driving&layer=traffic&destination=[YOUR_LAT],[YOUR_LNG]");
    else
         window.open("https://www.google.com/maps/dir/?api=1&travelmode=driving&layer=traffic&destination=[YOUR_LAT],[YOUR_LNG]");
}