Contact management with Google Cloud for chatting app

I need an android application for doing contact management for the chatting application that I am developing. UI for this app is not critical but functionality should be preset covering all of below points: 1) When user launches app for very first time then all his contacts should be sent to Google cloud - with international number format so that friends can be discovered easily. I am open for the component selection in Google cloud. App should also send person's profile - name, number and profile pic. May be all this data can be saved in Google Cloud Big query component. 2) In response to the query for point 1, app should receive list of friends which are also registered to this app - with name, number an profile pic. Extra points if you can include the groups to which he is part of - like whatsapp. 3) Anytime user changes his\her profile (name or picture), all the users from this contact should get an update automatically. Similar logic applies if user edit or delete any contact in his\her contact book. I am open to minor modifications or improvements in this and also use of appropriate component of Google cloud platform. App must optimize\minimize the number of transactions with Google cloud to achieve this functionality. user of material design in the app is preferred. I expect working solution with examples for this. You can use any 3rd party library you want as long as it's stable and proven.