spaCy - spaCy is a library for advanced natural language processing in Python and Cython.
Tesseract - Tesseract is an optical character recognition engine for various operating systems
monkeylearn - Text Mining Made Easy. Extract and classify information from text. Integrate with your App within minutes.
Onlineocr.net - Free Online OCR service allows you to convert PDF document to MS Word file, scanned images to editable text formats and extract text from JPEG/TIFF/BMP files
Google Cloud Natural Language API - Natural language API using Google machine learning
ABBYY FineReader - ABBYY's latest PDF editor software, FineReader 16 you can easily convert files like PDF to Excel, PDF to Word, edit, share, collaborate & more with this PDF editor!