Astar can also be used for non-grid structures. It can actually be used for any graph traversal, including e.g. Google Maps Navigation type use cases, and is ar

Astar can also be used for non-grid structures. It can actually be used for any graph traversal, including e.g. Google Maps Navigation type use cases, and is arguably even more suited to those problems than grid movement, since the lowest-cost path through a grid is often a very unnatural way to move through an open space, especially if you're using Manhattan distances.