Icon image comes from:
https://openclipart.org/detail/22309/apple-icon
and is public domain.

Icon resources were generated using:
http://romannurik.github.io/AndroidAssetStudio/icons-launcher.html
with settings:
http://romannurik.github.io/AndroidAssetStudio/icons-launcher.html#foreground.type=image&foreground.space.trim=1&foreground.space.pad=0&foreColor=607d8b%2C0&crop=0&backgroundShape=none&backColor=ffffff%2C100&effects=none
which produces art under CC 3.0:
http://creativecommons.org/licenses/by/3.0/
