In Bitrix24, you can bind CRM items to the workgroup tasks and calendar events.
Tasks and CRM
To connect workgroup tasks with particular CRM items, open the task form, click More and find CRM field. Select leads, contacts, companies or deals you'd like to bind the task to. You can connect your task to several CRM items at once.
When you have several tasks in the same projects bind to CRM items, you can easily navigate between them in the list view. Add CRM items column to the list in the settings.
Calendar and CRM
You can connect workgroup events to the CRM items as well. Open the workgroup calendar and open event form. Find the Select CRM items field in the More section. Add leads, contacts, companies or deals. You can add several items at once.