How can I specify exact coordinates?

There are two ways to do this, currently:

1. On the Locations page, import a KML file containing the Placemarks you need
2. Edit the URL in your browser address bar to set exact coordinates

If you enter coordinates into the search field, the app will return the nearest known place to those coordinates, rather than going to the exact coordinates, so avoid doing this if you're looking to set the red pin exactly.