I have done extensive research in past when i was considering switching from mac to linux. Came to the conclusion that there is no viable open source alternative for the mac preview app unfortunately. My requirements where: - Fill forms. - Add text and markup. - Reorganize/add/remove pages. - Redact parts of the document. (should also safely delete underlying text data, without rasterization of the whole document) - Add image of signature without rasterization of the whole document. This [1] is a long discussion i found about the topic.

[1] https://unix.stackexchange.com/questions/85873/how-can-i-add...