I've got a collaborative editing project and I need to be able to ink on large files and then save to a shared Google Drive. Xodo just gives up on saving things eventually and runs into permission errors trying to save to google drive. NeoReader on the boox just didn't save the ink on the first 28 pages when exporting. Samsung Notes can't handle files bigger than 100MB. OneNote is not a good solution for exporting unless I'm missing a workflow option. OneNote is kind of being a pain in general lately.
What are you all currently using for PDFs?
<sigh>
I downloaded way too many apps to try out. I even paid for a nice journal app that comes with some really pretty templates. But it looks like I'm stuck with Xodo for big files. Syncing across Samsung Notes is so nice, but it can't do big files and they killed the windows app on non-samsung computers. I've watched a lot of reviews for Penly and Noteflight, but I'm not convinced enough to pay for those as well. Finding ones that work on the boox tablets is weird as well. Some apps show as not compatible with the mini for reasons.
My wife has been using Kofax Power PDF for a few years and seems to like it. However, she uses it primarily to convert between PDF and PowerPoint. Having very little experience with the app, I don't know if it will serve for your purposes, although it does handle inking and I have helped my wife export some really big PDF files (she writes English grammar books for non-English speakers, so the files are very heavy on graphics content). The app was a one-time purchase and I think there have been a few (free) updates offered along the way. Kofax makes a few different PDF products:
Kofax Power PDF Standard Version 5.0 (trustedtechteam.com)
Convert PDF To PowerPoint - Made Simple With PDFaid
They'll all now subscription based. I use Xodo on both Windows and Android. Sometimes I use Drawboard on Windows. Free versions of course.