Do you see an "emulators" property in the returned JSON?
If you don't that means CQ doesn't think the resource type for the current page is a mobile page.
To verify this head on over to the OSGI web console http://localhost:4502/system/console/configMgr and search for "MobileEmulatorProvider". Make sure your site's page component or some parent page component is listed as one of the mobile resource types. If your resourceType is not listed it probably means your OSGI Config is not setup correctly. Verify the name of your config.xml is unique (ie. don't copy the geometrixx sample without renaming it first).