smash.gg - An esports platform empowering bottoms-up growth of competitive communities with value-add services...

Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.

Challonge - The Ultimate Source for Tournament Brackets

Eventbrite - Discover Great Events or Create Your Own & Sell Tickets

Competize - Competize is a SaaS-based league and tournament management solution that offers deep fan engagement, live score management, software for scheduling, sponsor promotion, delegate administration, database in the cloud, and much more.

Bylde - Bylde is a SaaS platform you can use to Start, Manage and Grow your groups and communities.