Am using a 1024x1024 texture, which am mapping to a quad in Unity3d. The target platform as of now is PC standalone. This is how it looks:
You can see how pixelated and blurry the objects in the screen are, how can I make it more readable and less pixelated?
Import settings, quality settings and a screenshot of the scene with mip-map turned off here. The texture and the quad asset can be found here.
The image looks fine to me: it looks like a 3D video game.
Note that 1k is very small to use as a PNG for the texture for an object which will appear that large in your final scene.
Secondly click on the texture, and then Inspector
.
Note particularly the "Max Size" setting, which indeed should be bigger than the literal size of your PNG. Learn about the "Mip Maps" concept as anim_it says. Also note your "Filter Mode". And indeed the "Texture Type". These settings all need to be "just right" for a given game situation.
Particularly read the two comments by Kolanda above which well-explain anisotropic handling: If you see an object at low angle, like a floor or your cards, it tends to lose texture resolution fast. Try to use "anisotropic" as your filtering mode and see if it helps - it was invented for such situations. As a test move the camera, to view the table from above, to separate texture-related issues from view-related issues.
You should probably include a screenshot of your Inspector for the texture, to get more detailed help. BTW the quad you are using is totally unrelated.