If you’re used to a program like Acrobat Pro, you may have some difficulty adapting to PDF editing on Linux. There’s no single standard tool that supports all types of editing. Ubuntu ships with Evince (GNOME Document Viewer) which is mainly used for reading PDFs. You can use it to add annotations, but that’s about it. For further editing, you’ll need a different program. For instance, if you have a straightforward requirement like inserting your e-signature, you could try Xournal. Or, if you want something similar to Acrobat Pro, Master PDF Editor is a well-rounded option with a ton of features. LibreOffice Draw We’ll cover LibreOffice Draw first as it’s preinstalled in Ubuntu, easy to use for basic editing, and just convenient overall. LibreOffice Draw is a vector graphics editor but it also works decently for editing PDFs. Just remember to Export directly as PDF instead of saving normally (Ctrl + S). Getting back to its features, some of its common uses include: Text editing Annotating Inserting images and signatures Editing the outline Merging PDFs Creating fillable forms LibreOffice Draw is better than other built-in options like Gimp or Okular (Kubuntu). It does have a reputation for messing up the formatting sometimes, in which case, you can try other alternatives from this list. Master PDF Editor As stated, Master PDF Editor is the most Acrobat-like option and also the best program overall for editing PDFs on Ubuntu. Some of its main features include: Great customizable UI Can modify texts and objects Annotating Creating and filling in forms Merging and splitting PDFs Rearranging and resizing pages Image insertion Digital signature (creating, signing, checking) The free versions (v4 or older for watermark-free outputs) cover the requirements of most users. For advanced editing, there’s a premium version with extra features. Xournal++ While Xournal is technically a note-taking software, it’s also popular among users that specifically need to add texts, images, and annotations only to PDFs. It adds such content as an additional layer, meaning the original PDF data (vector objects and so on) aren’t modified in any way. PDFArranger Like Xournal, PDFArranger is another small tool with a niche use case. It’s excellent if you just need to merge or split PDFs, or just edit the pages in general (rotate, crop, rearrange, etc.). Inkscape Inkscape is a vector graphics editor like LibreOffice Draw. It supports many of the same features as LibreOffice Draw (image insertion, text editing, signatures, etc.), making it a viable alternative. Comparatively, its feature set for editing PDFs is still limited though. For instance, you can only import and edit one page at a time. Sejda Sejda’s feature set is more of the same. It does most of the things other editors like Master PDF Editor do (text editing, image insertion, merging/splitting, formatting, page editing, signatures, compression, and so on). What sets it apart is that you can also edit online. Unlike most other ‘free’ editors, Sejda’s free version does all of this without adding any watermarks to the end product. But there are certain limitations (e.g., daily cap on how many edits/saves you can make).