interface - How can I add a high quality design to my Android application? -

I have just finished my first professional application for Android. The problem is that the interface looks like a school project . I tried to find professional templates for background and buttons and controls, but I could not find anything.

Where can I get stuff? Try it:

Try it: After some time you think some simple visual design changes But I'm getting a good way of doing this. For taking signals from such examples, who are really good already, but just touch them according to your needs (eg colors etc.).