Update-MapsHERE has updated the maps data for Windows Phone devices. You can go to Map—> Download Maps—-> Check for updates and my Lumia 630 is already updating the downloaded map. The update size has been kept to minimal as it brings only the data which has been refreshed.

Changes:

Much better street network coverage

Better 3D landmarks

Location addresses on map for more countries

HERE has also announced a Bug Fix for recently updated HERE Maps app for Windows 8.1 devices. The last update brought Manual positioning, waypoints and Redesigned city pages long with global availability.

Windows 8.1 app link

Windows Phone app link

Read more here