I was using Moon+ reader, but it has a pause at each chapter and ads.
It’s not open source but honestly, I find google play books the best one :))
Librera.
It’s the second best e-book reader across the board, and the best open source one
Moon+
Best ebook app out there. Stable, smooth scrolling, damn near infinite visual arrangements, broad range of settings in general, option for either folder of bookshelf based browsing (matters a lot if you don’t have all your files’ tags perfectly arranged), works well on any kind of screen, and even old devices don’t lag with it under most circumstances.
Is your Kindle e-ink?
The general issue with e-ink-based readers and scrolling is that e-ink is designed to be mostly static, with sporadic (preferably partial-page) refreshes; but scrolling needs to have a very high refresh rate that updates the whole page simultaneously if it’s going to be usable.
Yeah that’s the problem. I would change the OS but your battery life would go to s***.
I also prefer scrolling ebooks, and I settled on Librera. I have not found a way to get rid of the blank newline between each “page”, but it’s still better than turning pages.
I use Koreader on android with scrolling, also side loaded it on my Kobo e-reader (but I prefer paging on eink) you might be able to get it on kindle too