Project Planner Viewer allows you to visualize the contents of PPF files. So, it can be used as a complement for Project Planner and Project Planner HD. The application lets you keep track of the different tasks and phases of a project.
The application has a straightforward interface, which has tabs that generate different views of the project you have loaded. In this regard, the first tab visualizes tasks as a Gantt chart, which in turn, can be organized by day, week and month. It is good that a system of colors is used to indicate task progress. There is another tab that shows the planned resources per day. Again, different colors are used to show usage levels. Finally, you can go to the Project Report tab to generate a report about the current level of execution of the different tasks in the project. In all cases, it is possible to send the charts and reports to printer.
All in all, Project Planner Viewer is an inexpensive way to share projects with others. Still, I should alert you that this app is not intended to edit projects. It is shame that the product seems to be very unstable: at times it crashed, at times it did not start at all. However, if you are interested in trying it for yourself, it is available from the Mac Store at no cost.