Open Source Alternatives to Xodo

Switching from Xodo to Okular or Xournal++ addresses the fact that, despite being free, Xodo’s source code is closed and unpublished — for anyone who specifically wants an auditable, open source PDF tool rather than merely a free one, that distinction is the whole reason to switch. Okular covers the same core annotation and form-filling ground as Xodo, plus support for extra document and ebook formats beyond PDF. Xournal++ instead focuses on pen-based handwriting over a PDF background, a closer match for tablet users who annotate by hand rather than by tapping and typing. What neither fully replicates is Xodo’s polished mobile apps and built-in cloud storage integration for Google Drive, Dropbox, and OneDrive, which are more central to Xodo’s design than to either open source alternative.