Sony Mobile has update Sketch app to version 6.4.A.0.3 which brings new improvements. So this will replace the previous version 6.3.A.0.6. This is a major update as this update brings the compatibility to Android 6.0 Marshmallow. As usual there are bug fixes and performance enhancements. See the full change-log below.
Android™ M support
More robust handling when Sketch is in the background