Consider this scenario : There are two activities Activity A do network call and display count of tasks and the Activity B fetch tasks from database, or from same network API call if data is not available. While A is busy in network call user can traverse to Activity B. I am using **Retrofit2** and **Rxjava2**. 

My question is when Activity A is doing network call and user go to Activity B, and still the network call is running then, I want the object of Observable<> created on Activity A,also on Activity B because if I do not get callback then another network call for same task would be done on Activity B which is not feasible. 

Anyone have idea How I can persist object of Observable<> created on Activity A ,by using this observable object I will get callback on Activity A as well as on Activity B and do some functionality.