For an APK to be installable, it must be signed: <https://developer.android.com/training/articles/keystore>

For that purpose, create a keystore by executing this command:

    keytool -genkey -v -keystore ~/.android/scrcpy.keystore -keyalg RSA -keysize 2048 -validity 10000 -alias scrcpy -dname cn=scrcpy

(Adapt ~/.android/scrcpy.keystore if you want to generate it to another location.)

Then create server/keystore.properties and edit its properties:

    cp keystore.properties.sample keystore.properties
    vim keystore.properties  # fill the properties