Google Map Gradient Polylines for Android?

It looks like this is not implemented yet in Google Maps Android API.

You can see the following feature requests:

https://issuetracker.google.com/issues/35828754

https://issuetracker.google.com/issues/35821835

At this point I think Google didn't set a high priority on these tasks. You can star these feature requests to add your vote and subscribe to further notifications.

It is is available from Maps SDK 3.1.0 (beta): https://developers.google.com/maps/documentation/android-sdk/v310-beta#creating_a_gradient_polyline