Hi Dennis,
Calendars are available in Quick Base as a type of report, so long as you have date fields in your records when you go to create a new report you can select calendar as a report type. From there it will ask you which fields you want to base the calendar dates on and then also which ones you would like to display. In your instance it sounds like within your tasks table you would want to have a report that showed your customer's names and the date of their task on the record and most likely base it on the follow up dat field. Then when people click into an entry on the calendar they would be taken to the individual task records related to your clients. I hope this information is helpful.
Calendar help doc------------------------------
Evan Martinez
Community Marketing Manager
Quick Base
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