Sure, by much worse I mean that with integer scale the game screen looks much smaller that with scale outer, so the pixel art looses even more pixels in my mobile phone.
I see, I'm going to investigate about that, thanks for the ideas.
I see. Well, you said your phone has a resolution of 800*480, while your game is designed at 480*320.
This means your mobile screen cannot fit a scale of 2 for your game, since that would require 960*640 or higher. So your game would stay at a scale of 1 using integer scale I believe. Which would look rather small indeed on a 800*480 screen.
In this case you could still use a scale of 2, but make the level area scrollable, so it can actually all be seen by the player. The other options really only are to have it rest at regular scale, resulting in a game area too small or to use non-integer scaling, which will mess up the pixels.