TextSniper - Instantly extract any text from your Mac's screen
TinEye - Reverse Image Search to help find an image's source, duplicates or altered versions.
LensOCR - Scan anything from your Mac's screen.
GImageReader - gImageReader is a simple Gtk/Qt front-end to the Tesseract OCR Engine.
OwlOCR - OwlOCR offers simple optical character recognition of text in PDF files, images or on-screen and converts that to plain text.
Microsoft Lens - Microsoft Lens (formerly known as Office Lens) is an all-in-one application designed for Windows, Android, and Apple devices, allowing you to capture important information from signs, PDFs, whiteboards, and more to add.