In my app i need something like that.In my app a user can easily be a member by signing up.Now when a user become a member then he can communicate with other members.Suppose a want to send a message(same message) to all users, same location as he is.Or it may be something like that a user want to send a message(same message) to another 5 users whom he knows.
How can i do that.
I googled may times.I thought web-service can do that job.But i didn't right way to do that.
Can anyone how can i do that with references ???