User Groups

• NYCJUG - New York City J Users Group with meetings on the second Tuesday of each month.
• British APL Association (BAA) - has a bi-weekly on-line meeting.
• APL germany e.V.
• AFAPL - Association Pour la Promotion des Languages APL et J
• ACM SIGPLAN - Array-Programming Chapter of Special Interest Group on Programming Languages.
• JAPLA - Japan APL Association, for APL and J.

Social media

• reddit group

Others

• 🇰🇷 한국 J 언어 사용자 모임 - Korean J User Group with mailing list at Google Groups.
• APL language FAQ for other APL and J related user groups; FAQ (10) "What user groups exist?" (dated list, about 2/3 down the page)