To view your login history, log into your LeadSimple account. Click your name in the top left corner to access your profile page.
Under the section Login & Security, click the link "Login History". This will open a tab that will display all your log in history.
Note that this link will only show the login history for the current account you are logged in on. You will not be able to view other users' login history. (Note also that it only records log-ins, not user activity.) If you need that info on other users', please reach out to firstname.lastname@example.org or use the chat-box in the bottom right corner of this page.