An fwknop client is available for Android
Also, the APK is available for direct download.
Version 1.3.1 is a minor bug fix version and is now available!
Version 1.3 of fwknop-gui is available!
Version 1.2 of the Android app is available!
Fwknop-gui and the entire fwknop ecosystem was featured on FLOSS Weekly, recorded live on September 1.