The Artstor Digital Library is a nonprofit resource that provides over 1.6 million digital images in the arts, architecture, humanities, and sciences with an accessible suite of software tools for teaching and research. Collections are used for teaching and study in a wide range of subject areas, including art, architecture, music, religion, anthropology, literature, world history, American Studies, Asian Studies, Classical Studies, Medieval Studies, Renaissance Studies, and more.
Artstor is more than art: www.artstor.org/subjectguides
Artstor Mobile: www.artstor.org/mobile
Some areas of Artstor require the user to "double-click" to get to materials.