ProtOnViewer 1.4.1 for Mac was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. This app's bundle is identified as com.prot-on.ProtOnViewer. This free Mac app is a product of Prot-on.
The most popular version among ProtOnViewer for Mac users is 1.4. The software is included in Productivity Tools. Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe.
From the developer:
Prot-On is revolutionizing the way to protect the files you share, allowing you to decide and track at any moment who, how and when their content is accessed
You can protect photos, documents and texts directly on your mobile and keep control of any existing copies wherever they might be (in the cloud, in other phones, computers or storage devices).
You may want to check out more Mac applications, such as Combine PDF's, ShinyDroplets2 or MakeDocJ, which might be similar to ProtOnViewer.