So I needed to read a ByteArray from the InputStream in Android. Therefore I used this custom method in java in a kivy App using pyjnius for the same reason as stated in the link. I placed the ReadInput.java file in this directory: ~/Build_Environ/.buildozer/android/platform/build/dists/JniusPrintBluetoothAppie/src/main/java/org/kivy/android I initialised the java class with pyjnius: The java code: I read from the buffer in