In doing some research for the native american heritage month posts, I came across this interesting list on Wikipedia:

endangered Native American languages with mobile apps

Language revitalization, also referred to as language revival or reversing language shift, is an attempt to halt or reverse the decline of a language or to revive an extinct one. . . . A community often sees language as a unique part of their culture, connecting them with their ancestors or with the land, making up an essential part of their history and self-image. Wikipedia