Question About Design

I am working on my first app for android and i got a problem i dont know how to solve…hope you can help me
i got the code almost finish and started design my app with photoshop, and it looks amazing and the way i like it on the computer, but once i make an APK and try it on a mobile phone it looks really bad in terms of quality (bad pixels and staff) now i’ve tried to go according to Supporting Multiple Screens By Android and made different design for every size and density, but that also did not work and the design looks bad and stertched…what can i do??

What’s the canvas size you are working on??

I’ve tried 480X800 and some others… no matter what it’s always stertching the design… am i suppose to make like 50 different design for each phone size? that doesnt make sense =