Active devices is a feature that will be providing in upcoming releases.
For the time being if you are having issues with accessing Pik TV on multiple devices, this post by KHR may help https://forum.telus.com/t5/Pik-TV/Pik-TV-with-Apple-TV-2-issues/m-p/117785/highlight/true#M4230
"You should absolutely be able to stream on 2 devices at the same time, across mobile devices including iPads, Apple TVs, browsers and supported Android TV devices. I would recommend logging out of all instances of Pik TV across your devices to reset your login tokens – you should only need to do this once. You could also log out of the TV provider log in on Apple devices on the chance that the issue is on Apple’s end. To do this on Apple TV, go to the Apple TV home screen --> Settings --> Users and Accounts --> Apple TV Accounts --> TV Provider --> Allow TV Provider to Access --> Off. You may need to log back in to the Pik TV app with your My TELUS username and password the first time, but after this, your credentials should be maintained. Let me know if this resolves the issue!"
