in the service , you may purchase , with `` real world '' money , a limited , personal , non-transferable , non-sublicensable , revocable license to use -lrb- a -rrb- `` virtual currency , '' including but not limited to virtual gems , solely for use in the service , and -lrb- b -rrb- `` virtual in-app items '' -lrb- together with `` virtual currency , '' `` virtual items '' -rrb- .