Paperwork is described as 'OpenSource note-taking & archiving alternative to Evernote, Microsoft OneNote & Google Keep' and is a popular Note-taking Tool in the Office & Productivity category. There are more than 100 alternatives to Paperwork for a variety of platforms, including Online / Web-based, Windows, Android, iPhone and Mac. The best alternative is Joplin. It's not free, so if you're looking for a free alternative, you could try Standard Notes or Microsoft OneNote. Other great apps like Paperwork are Notion (Free Personal), Evernote (Freemium), Simplenote (Free, Open Source) and CherryTree (Free, Open Source).
Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, can be copied, tagged and modified either from the applications directly or from your own text editor.