We have a small app with Restlet on the GAE server and GWT and Android clients. Restlet serves GWT-serialized replies to GWT clients and JSON to Android clients.
All
Just to let everybody know: I managed to get GAE+Restlet+JSON+GWT working after much fiddling. The process was really chaotic (reminded me of days programing for the Win32): I was just changing settings until it started working.
The problem that I was having is:
I'm not going to use Restlet for the following reasons (hint to authors):
Since then I switched to Jersey.