Cdavid

Thank you for clarifying

A web browser which puts everything in a cache, so you can continue to read, if offline.

Ceno does that but it's for mobile

Good to know, I appreciate you taking the time to clarify it to me, thanks

Very interesting, thank you for clarifying and the other informations, i might look if I can find an used Kobo h2o

Thanks, I'll try it

Thank you for taking the time to share it with me, I am a bit familiar with it, I used it to convert formats before but I ended up using shell/python scripts in the end to be more sttaightforward converting files, I will look more into it as soon as I get an E ink to try it out on book transfers, I have bought books outside Amazon and it'd be very helpful for me to have Calibre then

It appears so to really be discontinued but it'd not be a dealbreaker for me, I hate constant updates (i know security updates are for good but still annoying, i dont know if E inks do security updates like usually on mobile/PC though, do they?), interesting about the book transfer, is it natively supported by the device or do you use something like Calibre (which would be fine too)? Waterproof could also not be a dealbreaker for me I guess I could buy a case for it? I certainly wouldn't stand in the middle of a rain to read

Is it safe as PDF (i know PDF can be virus ridden by usually embedding the virus in specific parts of the PDF layers or so I heard a while ago, which I usually am careful what PDF i open) or more/less?

Thanks for the input, I do occasionally read manga/comics but it'd not be a dealbreaker for me to compromise on it for a while

Kindle is very affordable but can you jailbreak non-Paperwhite Kindles too? I thought Kindles were very strictly hard to jailbreak while keeping it usable

Maybe I misunderstood but what OP means (that I understood) are softwares that you don't need to rely on internet connection to use it, probably ones you need 0 need at all of internet connection but I assume OP may also be accepting suggestion of ones you can open while without internet connection but also be able to download data for offline use (maybe like Language Transfer).

For language learning there's Language Transfer (it's also open source)

I never truly understood the use of epubs to be honest, I usually convert them to PDF. Also I didn't know you could do crossword puzzles on E ink that does sound very nice, so I assume you could do Sudoku as well? I have heard of reMarkable and it sounds perfect for me but its not within my reach atm unfortunately. I never heard of Boox so I will check it out. Is Kobo durable too?