I like that it is so easy to use from any device (mobile or desktop) - It's very simple! We've been using this tool since January 2017 but we have no complaints yet about its usability at all. The support team was always quick in responding my questions which were asked via email/chat during business hours. They also work closely together with Google Calendar allowing us access our calendars through their app too. Nothing really right now because there are not many features available compared other similar tools out here. But if you're looking into something free without much additional cost then definitely try them first before going ahead. This has helped me manage appointments better than having paper copies of schedules around office space where everyone can get confused when trying to read who will be attending meetings next week etc.
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