In the case of Communities like KeralaJUG or Hackster whatsapp is helpful for faster growth but still it's not feature rich! Its not possible to manage members and control spam or junk posts from members in whatsapp. And the cloud syncing feature of Telegram is a good advantage for community groups for sharing contests. In Telegram a newly added member can access all the past conversation happened prior to him which is a very good and necessary feature for groups which are made with serious aims.
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