When you open an existing PDF file in PDFpenPro, the application automatically detects whether the document you're working with is a scanned image or already contains selectable text. The application's OCR tools are rock-solid. Additionally, you can create PDFs from scratch, create or edit forms, and create tables of contents for your PDF documents. With full PDF-document editing, you can make changes to text and replace images in PDF documents. PDFpenPro is a standout for Mac users thanks to its solid features, not the least of which is an excellent OCR engine.
(That version, PDFpen, is available for iOS devices as well as Macs.)
It's also available in a less expensive version with fewer editing options. PDFpenPro is a macOS-only PDF editor that's been available for many years.