Development & Integration - Whatsapp API

Looking for an expert developer who can develop an application which can send broadcast message[s] to groups/ individuals. I already have a user management portal and want the developed script in that ONLY. Entire Flow of Application: # Admin will create Account [Already working with my script] # USER Login # Add Members, Authenticate their Numbers # Create Group # Add Members in the Group # Create Broadcast Message and Send # Others requirement will be added [in scope] #### Instead of sending long portfolio, Let me know your relevant experience [APIs] and When you can start and finish the project, >>>> Limited Budget, Limited Time, Be responsive while gathering the project. >>> Bid on THIS PROJECT only if you have time.. I can't stay for few weeks.