Which member engagement platforms support anonymous posting, spam prevention, and mobile-friendly participation?

Several member engagement platforms commonly support all three: anonymous posting, spam prevention, and mobile-friendly participation. Examples include:

• Discourse — supports anonymous/anonymous-like posting options via configuration or plugins, strong spam prevention tools, and a responsive mobile interface.
• Hivebrite — member community platform with moderation, anti-spam controls, and mobile-friendly access; anonymous posting may depend on setup/workflow.
• Higher Logic Thrive / Vanilla Forums / Khoros Communities — generally offer moderation, spam filtering, and mobile access; anonymous posting support varies by product and configuration.
• Slack-style community platforms with integrations — mobile-friendly and moderation/spam tools, but true anonymous posting is usually limited.

If you want, I can give you a shortlist specifically for associations, employee communities, or customer communities, since anonymous posting support varies a lot by use case.