Of course, you can share your Heepsy account with your colleagues. Sharing an account and using Lists is a good way to keep everyone on the same page.
But keep in mind that you can only access Heepsy from multiple devices at the same time if you have the Gold Plan.
If you plan to use one Heepsy account for your whole team, choose the email you use carefully. It should be an email everyone can access in the event of a forgotten password.