Reviewer
You can share a schedule you created or review a schedule that somebody else shared with you. To share a schedule with someone who has access to the resource scheduling apps, you add this person to the schedule, either as a maintenance planner or as a reviewer. The role you choose sets the level of access to your schedule
People that you add as a maintenance planner are co-planners with permission to change, share, freeze, and delete the schedule. Co-planners can also post and reply to comments in the activity log.
People that you add as a reviewer can view the schedule and post and reply to comments in the activity log but are not allowed to make any changes. They also don't see the utilization forecast shown in the Scoping and Refinement phases of a schedule.
Activity Log
The activity log helps you to keep track of the changes made by co-planners and reviewers of your schedule. In the log, you can also post and reply to comments.
If you and another planner are working on the same schedule at the same time, you can see the other planner’s changes once you refresh the app or make a change yourself. If the other planner starts changing an order operation before you do (for example, by rescheduling it), this change takes precedence over your change and you will see an error message.
In addition to showing changes made to a schedule, the activity log allows planners and reviewers to comment on a schedule and to reply to existing comments. Comments are visible to everyone with whom the schedule has been shared.