There was an interesting discussion before:
My needs can be summarized as: a stabler and robuster (and maybe cheaper) alternative to Marginnote (MN), focusing on note-taking, without mindmaps and study cards. I feel many others would share my needs, but strangely, I cannot find a single app alike.
I like the note-taking features in MN so much. In more details:
- The notes can be associated to an excerpt of the original texts.
- The notes/excerpts can be collected/selected by color and user-defined tags.
- The notes/excerpts can be searched, and moreover in the collections defined above.
- Global search in all notes.
- The notes can be batched edited (e.g. change color).
I also like the reading experience in MN:
- In-PDF bookmark support.
- Forward/Backward function.
- Double page reading.
- Cut/Enlarge margin space.
Although I also want:
- Multiple tabs (for multiple documents.)
Other things I care about:
- It supports iOS and Mac, with basically the same function.
- It saves notes separately, without changing the original PDF file. I also hope the notes can be exported in readable (and, better, open) format, but this is not very important for me.
- It supports epub, although I can give up this if the alternative works very well on other things.
- I hoped MN could be more optimized for Mac, but seems this is not their focus. For example, it easily takes more than 5GB memory with a handful of open files. And it does not look like a Mac app.
Even only considering the bold features (which I really want), I cannot find an alternative. Apps I have tried: Liquid text, PDF Expert, Hightlights, Foxit Reader, PDFelement, PDF reader, Flexcil, Goodnote, notability. For last three, I don’t that into hand writing when reading, so…
The closest is Liquid text. But it is very unstable and basically unusable on Mac (at least when I tried it several months ago), and it requires subscription for sync between iOS and Mac, which I feel unacceptable.