For small, local communities WhatsApp is a good choice. The main objection I've seen from people to join WhatsApp community is that it requires sharing your phone number with complete strangers. But if that is not a problem for your members, you can employ following strategies to grow your WhatsApp community:

1. First have a clear purpose and mission for your community.
2. Optimise community settings and profile to make the purpose clear to new members
3. Invite members from existing WhatsApp groups and your personal network
4. Incentivise inviting new members
5. Host AMAs, interviews with local influencers
6. Host events and make sure that attendees join your WhatsApp Group
7. Build a content calendar and stick to it.
8. Appreciate and motivate existing members to contribute more
9. Create polls, quizzes and discussions about latest trends and topics

These are 9 proven ways to get more members to your WhatsApp group. Of course, different type of groups on WhatsApp can grow their membership through other techniques.

I have two large WhatsApp groups - about 900 - 1000 members in each. We are strictly invite-only. Frankly speaking, I don't recommend building a community or group on WhatsApp; unless it's a family or friends group with casual chats.

Why don't you consider building your digital marketers community on Jatra? I'd love to join.