title: Android default theme
body: <p>I am making one android application but i was thinking about themes..</p>
  
  <p>If i don't declare a theme of  my Android application which theme will be used?
  Where i can find this information? 
  What is the criteria for use one and other?</p>
  
  <p>I was thinking about, if i want customize my all application, i have to extend one theme and custom all item that i want to customize.</p>
  
  <p>And what if it assumes one of them as default? Weather I have to customize it again? How do i know what is the default one?</p>