Keap

Keap started as Infusionsoft in 2001 and has evolved into a full-featured CRM for small businesses. It bundles appointment scheduling with email campaigns, SMS, and customer pipelines so you can handle bookings and follow-ups from the same platform. The integration means when a client books, it triggers your automation workflows automatically.

This works best if you need more than just a calendar. Consultants, coaches, and small service agencies get value from the combination of scheduling, automated reminders, and lead nurturing. It's a business system that happens to include bookings, not a scheduling tool adapted to add CRM features.