Historypin

Historypin lets you share historical pictures and stories by pinning them to a location on a world map. Google Street View can be overlaid with the historical photos for a modern comparison. Museums, individuals, local history societies, historical photo archives, newspapers and others have added content. Android, iOS and Windows phone apps are available.
TIP: Use Historypin as it offers a new and exciting way to explore and interact with historical images. It is a great place to add photos of places as they are placed in a historical context and linked to the actual place.