Privacy policy

Last updated: 13 August 2026

Vial collects nothing.

That is the whole policy, but a policy that says only that is hard to trust, so here is what the app actually does and why there is nothing to collect.

What the app stores

One file, on your device, holding:

• which levels you have solved, the fewest moves you solved each in, and the stars you earned;
• where you were when you last stopped, as the list of moves you had made;
• your settings — haptics, colourblind mode, reduce motion, dead-end alerts;
• a random identifier generated on your device the first time you play.

That identifier is not an account. There is no server for it to mean anything to and nothing to sign in to. It exists so that if progress from two devices is ever combined, each record can be attributed to where it came from.

Vial never sends that file anywhere. There is no server to send it to. You can move it deliberately, using Settings → Move progress to another phone, which puts your progress on the clipboard for you to carry across.

Your phone may copy it, though, and this is worth being exact about rather than leaving you to discover it. Vial's save sits in ordinary app storage, and both Android and iOS include that in the device backup they make of almost every app — Android Auto Backup on one, the iCloud device backup on the other. So a copy of your progress can end up in your own backup account, put there by your phone rather than by this app, and never anywhere we can see it.

That is deliberate, and it is the reason your progress survives a new phone without you needing an account with us. It is not instant — Android waits for the device to be idle on Wi-Fi and for a day or so to pass — so treat it as a safety net rather than a live copy. If you would rather it did not happen, it is your phone's own backup setting, and turning it off there turns it off for Vial too.

What the app does not do

• No network access. This is not a promise, it is a property of the build: the released app does not request Android's INTERNET permission, so it cannot open a network connection even if it tried. It has no analytics, no crash reporting and no advertising identifiers.
• Nothing that watches you. Vial uses a small number of open-source packages — to find a folder to save in, to play sounds, and to ask the store to show its own review prompt. None of them collects, sends or identifies anything. The claim above is about data leaving your phone, not about who wrote the code.

The one thing that leaves the app

Very occasionally, after a level you finished cleanly, Vial asks the app store to show its review prompt. That request does not travel over a network — it goes to the store app already installed on your phone, which is why it works without the app having internet access at all. The store then decides whether to show anything. Vial is never told what you did, or whether the prompt appeared. Nothing about you reaches us, because there is no us to reach — there is no server anywhere in this app.

• No accounts. Nothing to register, nothing to sign in to.
• No adverts.
• No purchases. There is nothing to buy, so there is no payment data.
• No permissions beyond what Android grants every app by default. The app asks for no camera, contacts, location, storage or microphone access.
• No tracking across apps or devices.

Children

The app collects no personal information from anyone, of any age, so there is nothing held about a child either.

Deleting your data

Uninstalling the app removes the file, and with it everything the app has ever stored. There is nothing held anywhere else to delete.

Changes

If a future version ever collects anything, this policy will say so before that version ships, and the change will be opt-in. Adding collection quietly is exactly what this document exists to rule out.

Contact

claude@vantilburg.me