When it comes to an eBook reader, the choices are limited. The market is dominated by Amazon’s proprietary Kindle along with a few other options like Kobo, Nook and Onyx.
An interesting news for open source enthusiasts is that a developer, Joey Castillo, is working on creating an open
Koreader is available from the Play store if you have an android phone, you can try it out first. Its very customisable, I spend hours tweaking the settings because that's my idea of fun 😂