PDF-X is described as 'Free Android PDF editor that works fully offline. Merge, split, compress, convert and annotate PDFs — no account, no subscription, no uploads' and is a PDF Editor in the office & productivity category. There are six alternatives to PDF-X for a variety of platforms, including Web-based, Windows, Mac, Android and iPhone apps. The best PDF-X alternative is Adobe Acrobat DC. It's not free, so if you're looking for a free alternative, you could try Smallpdf or iLovePDF. Other great apps like PDF-X are Qpdf Tools, I Love PDF 2 and XTPdf.