[immortal192]

I'm new to ereaders and have done quite a bit of reading. I know I'll want an e-ink-based ereader as it's better for the eyes (important to me since I'm on the computer 10+ hours a day already). I plan to read a lot of books, textbooks (about programming) and PDFs (articles). Obvious candidates for my budget of ~$300 is the Kobo Aura One and Kindle Oasis 2. The Paperwhite is also attractive since it's easily the best bang-for-the-buck, especially with the upcoming Paperwhite 4. And the new Kobo Clara HD should also be in the talks as it appears to be a direct competitor to the Paperwhite.

Anyway, it seems other than lighting and dimensions, there isn't too significant of a difference in terms of hardware, so I'm mostly interested about the software side of things (I don't mind installing firmwares, sideloading apps, or whatnot). So...

Are there lots of 3rd party features that can be added to both the Kobo and Kindle devices? Ae these in the form of "apps" where features can be added to an existing operating system or do they come as a whole package (all-or-nothing)? Are there third-party operating systems for these ereaders or is it expected that we continue to use the native operation systems and we just sideload apps that we like?

Things I like about the Oasis 2:

On the Oasis 2, there is vocabulary builder. This is crucial and I'm wondering if there is a similar feature for the Aura One. On a quick google search, I see that `MyWords=true` enables that. However, a vocabulary builder like the way Oasis 2 does it is practical: it gathers all your vocabulary words and then you can easily browse through them flash cards style with the term and the definition on the same "card". Whatever Aura One's implementation is should be similar--if it's just showing a history of words you looked up in the dictionary and then you get to select the word and it will find the definition again in the dictionary, then that's not ideal because it's not as fast and intuitive and you can't quickly switch between different words. I'm hoping someone can describe what vocabulary builder is like for the Aura One.

On the Oasis 2, there is multi-page navigation and quick reference to a different page via pop-up. The former is where you get a preview of a handful of pages in the form of large thumbnails--this is useful because you can find a page if you know generally what it looks like without needing to flip back and forth to find it. The latter is useful because you can quickly return to the page you're on after referring to a different page--again, no constant flipping back and forth. Is there something similar for the Aura One?

On the Oasis 2, there is a feature called "X-ray". It's actually really cool but potentially very gimmicky--I'm curious how you guys feel about it. I'm just wondering if it could be useful for using in textbooks where you want to find references to a certain term and more importantly the context. Is there an alternative for the Aura One?

It's a newer device--the Aura One is from 2016. On a side note, I'm surprised I haven't come across any news on the successor to the Aura One--isn't it time for a revamp?

Things I like about the Aura One:

The ComfortLight honestly seems like a must and might potentially be the deal-breaker for me for the Oasis 2 which doesn't have it. On the computer and phone, I use an application that adjusts the color temperature of the screen to ease my eyes and I can't imagine using my computer without it. I know that automatic adjustment doesn't work too well, but I don't mind manually adjusting it. For those who have both the Aura One and a Kindle, what do you think of this feature? Is it as useful as you think? I believe the Paperwhite 4 is expected to have something similar so that's something to consider.

It has a bigger screen. Someone said that it's not actually that significant because the amount of text displayed is similar due to how the Aura One has its margins or whatnot. However, I want to read some textbooks and PDFs and having decent size font and having as much words as possible on the screen is ideal.

It has more customizations on how a page looks (including fonts). I believe you can somehow load other "unsupported" fonts on the Kindle, and if you can, then perhaps these customizations might be overrated, since I've never actually heard of anyone complaining about the limited options by the Kindle in this regard.

I know that for a Kindle, you get a smoother and more streamlined experience in general, with a cleaner UI and less hard freezes.

It seems I should go for the Oasis 2, but I get the sense that there is a larger collection of apps to sideload for the Kobo than the Kindle. Is this the case? I feel like there is a bigger community of tinkerers and development/distribution of (open-source?) apps. As a programmer myself, I kind it view Kobo vs. Kindle as Android vs. iOS, in which case I prefer Android and therefore I should prefer the Kobo.

Any comments is much appreciated, even if it's to share your experience on a feature I've mentioned.

P.S. Some I have some assumptions--are these correct?

* Format of files don't matter at all for both Kindle and Aura one, since Calibre exists.

* Both continually receive updates and may have significant features added.

* All of these features work even for books/textbooks/PDFs/etc. If the source of these files was from my professor, for example, then these features will still work.