What are some alternatives?
Sorted - Sorted³ has been crafted to make scheduling quick and easy. Try it for a few days and it may very well become a productive, yet enjoyable part of your day.
Slater by Convergely - Schedule your Slack messages now, post them later
Todoist Smart Schedule - Todoist uses machine learning to predict your task due dates
HeyScale - Increase operational effectiveness with scheduled announcements and recurring reminders in Slack
Staffjoy V2 - Text message based employee scheduling app
MyTime Scheduler - The online scheduler connecting small businesses to clients