Kajabi - Kajabi is the only Knowledge Commerce platform today with everything you need to market, sell, and deliver your knowledge online.

PurpleTrail - Whether it is about birthday or wedding party or holidays, you just need to name the event and PurpleTrail will provide you the apt invitation solutions.

WildApricot - WildApricot is a powerful cloud software to help you automate and simplify membership tasks.

Evite - Send online invitations for all occasions by email or text message. Create invites for birthdays, baby showers, save the dates, or customize your own design.

Tendenci - Tendenci - The Open Source AMS is a cloud-based​ all-in-one management SaaS solution for Non-profits and Associations.

Zoji - As claimed by the developers of this Zoji, it caters online tools to aid you plan activities off-line.