What a 3D viewer app does with your files

A 3D model can be your own design, a client’s confidential part, or a paid file you are not allowed to share. Opening it in a viewer app should not send it anywhere. It is worth a minute to check what an app does before you trust it with files that matter.

Five questions to ask

1. Does it upload your files? Viewing a model does not need a server. An app that sends files away needs a reason you accept.
2. How does it get the file? A well-behaved viewer reads only the file you pick or share to it. Broad access to all your storage is a warning sign.
3. Does it need an account? If a viewer wants a sign-in just to open a file, ask why.
4. What does it measure? Many apps send usage statistics. The question is what is in them, and whether filenames or content could be.
5. How are purchases handled? Payments should go through the store’s own billing, not an unknown service.

Tests you can run yourself

• Read the store’s data safety section. On Google Play it lists what data an app collects and shares. Compare it with the app’s privacy policy.
• Look at the permissions. A viewer should not need access to your contacts, location or microphone.
• Try airplane mode. Switch off the network, then open a model. If viewing works fully offline, the app is not relying on a server to read your file.

What MeshView does

These are the facts from MeshView’s privacy policy.

• Files stay on the phone. Parsing and rendering happen locally. The app does not upload, transmit or copy your model files, their geometry or their colours. Opening and viewing work fully offline.
• It reads only what you choose. It opens a file when you pick it in the file picker or share it in from another app. It does not request broad storage access and cannot browse your device.
• No account and no ads.
• Anonymous usage counts. MeshView sends a small set of named events through Aptabase, a privacy-focused analytics service, such as that the app was opened, or that a file of a given format was opened, with a coarse size band and whether it had colour. Events do not contain filenames or file contents.
• Purchases for MeshView Pro go through Google Play Billing on Android and are managed by RevenueCat using an anonymous ID. MeshView never sees your payment details.

The full list of events and permissions is in the privacy policy.

Why this matters more for 3MF

A 3MF is more than geometry. It can carry slicer settings, project names and thumbnails, and sometimes more than you meant to share. That is one more reason to use a viewer that keeps the file on your device. See how to open 3MF files on Android.

A habit worth keeping

Treat a viewer like any other app that touches your files. A short check of its permissions, its data safety entry and its behaviour offline takes less time than a print, and it tells you whether your models stay yours.