Here i used meteor accounts-ui to add users, and mizzao:user-status to check users status
i created mongo collections chat rooms to store message, if chat room does not exit, it will create chat room for two users and store message in it.
to run this application open cmd and type git clone https://github.com/keshav-raj/simpleChatApplication.git press enter.
After download completed typr meteor npm install
now run meteor command