* [JavaMail](https://projects.eclipse.org/projects/ee4j.javamail). Copyright (c) 1997-2018 Oracle® and/or its affiliates. All rights reserved. [GPLv2+CE license](https://javaee.github.io/javamail/JavaMail-License).
* [Android Support Library](https://developer.android.com/tools/support-library/). Copyright (C) 2011 The Android Open Source Project. [Apache license 2.0](https://android.googlesource.com/platform/frameworks/support/+/master/LICENSE.txt).
* [Android Architecture Components](https://developer.android.com/topic/libraries/architecture/). Copyright 2018 The Android Open Source Project, Inc. [Apache license 2.0](https://github.com/googlesamples/android-architecture-components/blob/master/LICENSE).
* [dnsjava](http://www.xbill.org/dnsjava/). Copyright (c) 1998-2011, Brian Wellington. [BSD License](https://sourceforge.net/p/dnsjava/code/HEAD/tree/trunk/LICENSE).
* [Bouncy Castle](https://www.bouncycastle.org/). Copyright (c) 2000 - 2019 The Legion of the Bouncy Castle Inc. [MIT License](https://www.bouncycastle.org/licence.html).
* [AppAuth for Android](https://github.com/openid/AppAuth-Android). Copyright 2015 The AppAuth for Android Authors. All Rights Reserved. [Apache License 2.0](https://github.com/openid/AppAuth-Android/blob/master/LICENSE).
* [JCharset](http://www.freeutils.net/source/jcharset/). Copyright (C) 1989, 1991 Free Software Foundation, Inc. [GNU General Public License](http://www.freeutils.net/source/jcharset/#license).
* [Java™ Architecture for XML Binding](https://github.com/eclipse-ee4j/jaxb-ri). Copyright (c) 2018 Oracle and/or its affiliates. All rights reserved. [GNU General Public License Version 2](https://github.com/eclipse-ee4j/jaxb-ri/blob/master/jaxb-ri/LICENSE.md).
* [File Icon Images](https://github.com/dmhendricks/file-icon-vectors). A collection of file type/extension SVG icons, available free for use in your applications. [MIT License](https://github.com/dmhendricks/file-icon-vectors/blob/master/LICENSE).
* [GPX file type icon](https://www.flaticon.com/free-icon/gpx-file-format-variant_29258) made by [Freepik](https://www.flaticon.com/authors/freepik) from [Flaticon](https://www.flaticon.com).
* [Compact Language Detector v3](https://github.com/google/cld3). Copyright 2016 Google Inc. All rights reserved. [Apache License 2.0](https://github.com/google/cld3/blob/master/LICENSE).
* [ez-vcard](https://github.com/mangstadt/ez-vcard). Copyright (c) 2012-2021, Michael Angstadt. All rights reserved. [FreeBSD License](https://github.com/mangstadt/ez-vcard/blob/master/LICENSE).
* [Arimo font](https://fonts.google.com/specimen/Arimo). By Steve Matteson. [Apache License 2.0](https://fonts.google.com/specimen/Arimo#license).
* [Tinos font](https://fonts.google.com/specimen/Tinos). By Steve Matteson. [Apache License 2.0](https://fonts.google.com/specimen/Tinos#license).
* [Cousine font](https://fonts.google.com/specimen/Cousine). By Steve Matteson. [Apache License 2.0](https://fonts.google.com/specimen/Cousine#license).
* [Lato font](https://fonts.google.com/specimen/Lato). By Łukasz Dziedzic. [Apache License 2.0](https://fonts.google.com/specimen/Lato#license).