Utilizes commercial data for its maps. While not strictly better it can have more up-to-date map data than OSM with better coverage. This is also the reason for the the good address data.
After a Play Store update it is important to run the app once to download all the offline data again, otherwise it will not be usable when no external data is available.
Sygic's interface is tailored to navigation. While viewing maps in 2D is possible, it populates the map with a bunch of POI icons which detract from street names. The biggest issue is how easy it is to select something or start navigation when zooming in/out.