Supporting Multiple Screens

To simplify the way that you design your user interfaces for multiple screens, Android divides the range of actual screen sizes and densities into:

• A set of four generalized sizes: small, normal, large, and xlarge
  Note: Beginning with Android 3.2 (API level 13), these size groups are deprecated in favor of a new technique for managing screen sizes based on the available screen width. If you're developing for Android 3.2 and greater, see Declaring Tablet Layouts for Android 3.2 for more information.
• A set of six generalized densities:
  • ldpi (low) ~120dpi
  • mdpi (medium) ~160dpi
  • hdpi (high) ~240dpi
  • xhdpi (extra-high) ~320dpi
  • xxhdpi (extra-extra-high) ~480dpi
  • xxxhdpi (extra-extra-extra-high) ~640dpi

To create alternative bitmap drawables for different densities, you should follow the 3:4:6:8:12:16 scaling ratiobetween the six generalized densities. For example, if you have a bitmap drawable that's 48x48 pixels for medium-density screens, all the different sizes should be:

• 36x36 (0.75x) for low-density
• 48x48 (1.0x baseline) for medium-density
• 72x72 (1.5x) for high-density
• 96x96 (2.0x) for extra-high-density
• 180x180 (3.0x) for extra-extra-high-density
• 192x192 (4.0x) for extra-extra-extra-high-density (launcher icon only; see note above)