Baïkal - Cal and CardDAV server

FareHarbor - Reservation software for activity and tourism businesses. Low credit card processing rates, mobile friendly. Built for you.

Radicale - The Radicale Project is a complete CalDAV (calendar) and CardDAV (contact) server solution.

Travefy - The easiest online and mobile group travel planner!

SOGo - SOGo is groupware server with a focus on scalability and open standards.

Checkfront - Checkfront is built for Tour & Activity Operators, Rental companies and Accommodation providers. Manage your inventories online, centralize reservations, process payments and get unified access to leading distribution channels.