Do Resources on my project have to have OmniPlan instlalled?

I collaborate with free-lancers who do not own OmniPlan, yet I want them to participate in my projects, to at least visualize the project timeline and confirm whether they’ve completed their tasks or not. I do not want to give them full access to the project, and they do not wish to purchase omniplan. How can I collaborate in that way?

@jd12 You could share your OmniPlan content with them in a read-only format (PDF, for example), but if they would like to be able to modify the content within the OmniPlan project, they will need to be running OmniPlan on their Mac or iOS device.