GWT Feedback Tab

Is there a GWT implement开发者_运维技巧ation of a Feedback Widget?

There is no such widget that comes with GWT, but you can easily create one. The GWT Showcase shows many of the widgets that are available:

http://gwt.google.com/samples/Showcase/Showcase.html

However, as stated, you should be able to create a feedback widget fairly easily, by creating a UiBinder class (designed however you like), and creating a GWT RPC service to send everything over the wire. You can then process the provided feedback however you like in the service's server-side implementation (email it, store it in the datastore, etc).