How to use Android tablet as a ebook reader? If the screen resolution is high enough, there should be no difference between a tablet and an e-ink ebook reader (I read in several reviews). 

However, when I use my Android table (2560x1600) for reading by Adobe Acrobat, my eyes get tired soon comparing with Amazon Kindle.

I tried several bluelight filter, but it makes the color unnatural.

What are the best apps/ways to use an Android table for reading colorful PDF documents for long time without eye strain?
I think you misunderstand what e-ink is. It is nothing like LED or LCD pixels. Resolution has nothing to do with it.


Typical displays emit light. You can use them in the dark and they
will light up your face.
E-ink displays reflect light, like standard
paper. This is why they strain your eyes less.


As far as reducing eye strain with a non-e-ink device, try the following:


Use bright text on a dark background. Dark text on a bright background (such as this website) is typical however many find it to cause more strain. There are apps that will invert colors of a PDF for you. Depending on the app, images may or may not be inverted. (APV PDF Viewer is an example, although I haven't tried it personally).
Reduce the color temperature of your display. This means making the display's colors more "warm" (the colors are more red-ish), although after a minute your eyes will adjust and you won't notice. This can be done with an app (try Lux) which has the ability to automatically change the color temperature with the time of day.