Drawable or Mipmap ?? What's the difference?

The mipmap folder is exclusively for placing icons that will be used in the application.

Here's an explanation from Google about this case:

  

It's best practice to place your app icons in mipmap- folders (not the   drawable-folders) because they are used at different resolutions from   the device's current density. For example, an xxxhdpi app icon can be   used on the launcher for an xxhdpi device.

I hope I have helped.

They have been changed to mipmaps, leaving the drawable nomenclature only for PNG, JPEG, GIF or image files, 9-Patch files, and XML files that describe Drawable shapes or Drawable objects that contain multiple states (normal, pressed, or focused).

Briefly, mipmaps are used for application launcher icons. The Android system retains the features in this folder (and density-specific folders, such as mipmap-xxxhdpi) regardless of the screen resolution of the device where the application is installed. This behavior allows applications to choose the best icon / resolution for their application to display on the home screen. For more information about using the mipmap folders, see Managing Launcher Icons as mipmap resources.

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