If you are the admin of an app, you can decide how much your collaborators can view using your app's collaboration settings. If you go to your app's Settings > Collaboration tab and click on the dropdown next to a collaborator's email, you can select if they can "View Only," "View and Run as," or "View and Edit."

If you want someone to be able edit your app, but not deploy it to live, you can set their permission to "View and Edit" and then check the checkbox which says "Only dev version."