Creating quick icons for your android app can be a big task. AndroidAssetStudio has made task of re-sizing icons as per screensize very easy.
Android Asset Studio – Icon generators allows to quickly and easily generate icons from existing source images, clipart, or text. It’s free and online.
Icons can be also generated for Launcher icons ,Action bar and tab icons , Notification icons & Generic icons
It’s a great online tool in every android developers bag. We need to just upload original image , adjust and download zip file with all sized icon including folder structure.
Link to AndroidAssetStudio – https://romannurik.github.io/AndroidAssetStudio/index.html