Viewers who tune into the Super Bowl pregame show on Sunday will be treated to an unusual performance of “America the Beautiful,” which will be told, in part, through Native American sign language.

Sign language apps are learning tools that use images, videos, games, dictionaries, and interactive lessons to help people learn sign language on their smartphone or tablet. Share on Pinterest Sign ...

There is so much more to sign language than the hands, as interpreter Christine Dudley demonstrates. Carlo Allegri/Reuters Most people are familiar with sign language, the system that deaf people use ...