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.

Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.

SnapCalendar.io - Automate scheduling with our app: no more manual reminders. Reduce no-shows, boost visits.

Task Coach - Task Coach is a simple open source todo manager to keep track of personal tasks and todo lists.

SimplyBook.me - Online scheduling software that offers you a beautiful customisable booking website (or widget to your own website) to accept bookings and payments with the possibility of selling products as well.

Strikethru - Strikethru is a kind of to-do list notebook for managing work lists and staying updated with the important tasks.