If you're just trying to add geotagging to photos when they're taken, then you can turn this on under Settings, swipe right to Applications, scroll down to photos+camera. Make sure the box is checked for "Include location info in pictures I take".
If you're looking for an equivalent to the iOS map view that shows the actual pins on the map, I'm not sure if there's a WP app for that or not (I'm relatively new to WP). I think Picasa for Windows may do it, though.