Grocery Sync app times out (trying to connect to Sync Gateway?)

Have configured Couchbase Server and Sync Gateway on an Ubuntu 14.04 VM according to instructions on the Couchbase website. Have modified Demo.AppDelegate.Swift as follows:

private let kServerDbURL = NSURL(string: “https://192.168.1.12:4984/grocery-sync/”)!

Always get the following timeout (even with the Objective-C version of the app):

The request timed out. (error=Error Domain=NSURLErrorDomain Code=-1001 “The request timed out.” UserInfo={NSErrorFailingURLStringKey=https://192.168.1.12:4984/grocery-sync/_local/212cf102b9472e09ec096c744c6a205e4542f03e, _kCFStreamErrorCodeKey=-2102, NSErrorFailingURLKey=https://192.168.1.12:4984/grocery-sync/_local/212cf102b9472e09ec096c744c6a205e4542f03e, NSLocalizedDescription=The request timed out., _kCFStreamErrorDomainKey=4, NSUnderlyingError=0x16f394a0 {Error Domain=kCFErrorDomainCFNetwork Code=-1001 “The request timed out.” UserInfo={_kCFStreamErrorCodeKey=-2102, NSErrorFailingURLStringKey=https://192.168.1.12:4984/grocery-sync/_local/212cf102b9472e09ec096c744c6a205e4542f03e, NSErrorFailingURLKey=https://192.168.1.12:4984/grocery-sync/_local/212cf102b9472e09ec096c744c6a205e4542f03e, NSLocalizedDescription=The request timed out., _kCFStreamErrorDomainKey=4}}})