The release track to which the given file(s) will be re-assigned.
This can be the name of a
custom
track, or one of the built-in tracks:
- internal
- alpha
- beta
- production
For each release track, you have the choice of rolling the version(s) out
to all existing users simultaneously, or doing a staged rollout so that only
a fraction of your existing userbase will be able to download the new version.
For more information on using the internal, alpha, beta or custom testing tracks,
see the Google Play documentation:
https://support.google.com/googleplay/android-developer/answer/3131213
This field supports substituting environment variables in the form
${SOME_VARIABLE} or $SOME_VARIABLE at build time.