title: dpi of the image in the drawable folders
body: <p>I'm currently designing images in four different dimensions (ldpi,mdpi,hdpi and xhdpi) for an Android application. i know that the different drawable folders are used dependig on the dpi of the devices' screen.</p>
  
  <p>But what is the optimal dpi in photoshop to save the pngs? </p>
  
  <p>Should images for ldpi saved with 120dpi, mdpi with 160dpi and so on?</p>