The Change Tracking feature allows Teamwork users to follow any modifications made in the project by fellow teammates. This functionality was introduced in Archicad 24 and is only available with BIMcloud. (It is not a part of the BIMcloud Basic feature-set).
You can create a Subscription to a Set of Elements (filtered by Criteria, Selected Elements or Project Information). See the example below where a Subscription was created to track changes to a Stair:
When someone modifies an element you have subscribed to, you can click on the notification or the Tracked Changes Palette. Then you can double-click on it to see the details and choose to “Receive Changes and Compare” to open model compare: