Images seem fairly sharp on all of my Android devices, so I'm not sure why you would be seeing that. Which Samsung tablet are you using? If you go to Settings->Display Settings->Render Preference, you can switch between "Quality" and "Speed" which changes which PDF library is used. Perhaps one will work better for you than the other. This setting is only available on Windows and Android. I'm currently in the process of switching out the graphics library used in the Windows version (it was using Direct2d through Win2D and I'm switching to SkiaSharp which uses OpenGL, which happens to be what Android also uses), and I'm hoping this might increase the sharpness of the rendered images, but this may come down to the way that display scaling works in Windows, and I won't be able to achieve crisper images without rendering to a higher resolution, which takes more memory and processing time.
Mike
Mike