* [JCharset](http://www.freeutils.net/source/jcharset/). under [GNU General Public License](http://www.freeutils.net/source/jcharset/#license)
* [Android Support Library](https://developer.android.com/tools/support-library/). under [Apache license](https://android.googlesource.com/platform/frameworks/support/+/master/LICENSE.txt).
* [Android Architecture Components](https://developer.android.com/topic/libraries/architecture/). under [Apache license](https://github.com/googlesamples/android-architecture-components/blob/master/LICENSE).
* [colorpicker](https://android.googlesource.com/platform/frameworks/opt/colorpicker). under [Apache license](https://android.googlesource.com/platform/frameworks/opt/colorpicker/+/master/src/com/android/colorpicker/ColorPickerDialog.java).
* [colorpicker](https://github.com/QuadFlask/colorpicker). under [Apache license](https://github.com/QuadFlask/colorpicker#license).
* [dnsjava](http://www.xbill.org/dnsjava/). under [BSD License](https://sourceforge.net/p/dnsjava/code/HEAD/tree/trunk/LICENSE).
* [OpenPGP API library](https://github.com/open-keychain/openpgp-api). under [Apache License 2.0](https://github.com/open-keychain/openpgp-api/blob/master/LICENSE).