NewPipe-app-android/doc/gradle.md

Custom gradle parameters

You can use these parameters by specifying them inside the gradle.properties file as systemProp.<name>=<value> or passing them through the CLI with -D<name>=<value>.

packageSuffix

This allows you to specify a suffix, which will be added on release builds to the application id, the app_name string and the apk file.
No validation is made, so make sure to pass in a valid value.

skipFormatKtlint

This allows you to skip the formatKtLint task.
No value is needed.
It is used for CI in order to check for badly formatted files.