Google Lens - Discover information about something by taking a photo
CamFind - CamFind is the very first mobile application that can photograph, identify, and provide information...
GImageReader - gImageReader is a simple Gtk/Qt front-end to the Tesseract OCR Engine.
ShopSavvy - Shopsavvy title.
OpenScan - FOSS Document Scanner
TinEye - Reverse Image Search to help find an image's source, duplicates or altered versions.