How to convert PDF files to Grayscale Using Sejda PDF Editor?

'PDF24 Creator' is a free Windows-based PDF editor that provides a range of editing features.'

For Windows, Adobe Acrobat and Foxit PDF Reader are highly regarded as reliable and feature-rich PDF software. On Android, Adobe Acrobat Reader is a popular choice, known for its robust functionality. For Android, Adobe Acrobat Reader is often considered the best overall PDF app. It's a free, widely used app with a comprehensive set of features for viewing, annotating, sharing, and even basic editing.

To download a bunch of PDFs that contains a certain keyword using their link, use either of these downloaders:

• Batch Link Downloader
• iTextSharp
• URL Downloader
• Wondershare PDFelement

To convert a zip file to pdf, follow the steps given below: 

• Right click on the zip file.
• Choose Instant .pdf.
• Windows Explorer takes out the file and folders from the zip file and converts them to their PDF format.

There's no single best for everyone, as it depends on your needs and budget. Here are some popular options with different strengths:

• Free and Basic:
  • Adobe Acrobat Reader DC: Free, basic editing features like annotations and form filling.
  • Foxit Reader: Lightweight, clean interface, basic editing.
• Intermediate:
  • Sejda PDF Desktop: Affordable one-time purchase, advanced editing features like merging, splitting, and OCR.
  • Nitro Pro: Feature-rich, good for business users, subscription or one-time purchase.
• Advanced:
  • Adobe Acrobat Pro DC: Industry standard, professional editing tools, expensive subscription.
  • Nuance Power PDF: Advanced document conversion and security features, subscription or one-time purchase.