That is due to a difference in rendering between desktop and mobile
Desktop
- Direct3D (Windows)
- OpenGL (Unix, MacOSX kinda)
Mobile
OpenGL| ES is a stripped version of OpenGL for obvious reasons because you would not want a full fledged GPU API doing extra calculations on a device limited by a battery.
To get "good graphics" is entirely subjective and will be up to your own creativity.
All the above is not said to discourage, rather to make you understand that there are limits you will have to work within especially on mobile where you need to find the right balance between quality and performance.