Lost Canvas

Privacy Policy

Last updated: 1 September 2026

Lost Canvas is a single-player puzzle game made by Josef Cullhed. There is no account and no login, there is no advertising, and there is no third party involved: no analytics service, no advertising network, no data broker, no payment processor. Nothing about you is sold, shared or passed to anyone.

The game does send one thing, to one server, and this page is about that.

What is sent

Usage statistics, to api.cullhed.com, which is a server I run myself. While the app is open in front of you it says "still here" about once a minute, and it says so again when a painting is opened and when it is finished or left. Each of those messages carries:

• a random identifier the app made for itself on first launch (see below);
• the name of the app and its version;
• the platform it is running on — "ios", "macos";
• which painting is being worked on, and whether it was finished;
• a timestamp;
• on the once-a-minute message only, the number of seconds since the screen was last touched — a count of seconds, with no record of where the screen was touched or what was touched on it, so that an app left face-up on a table is not counted as an app being played.

That is the whole of it. It is used to work out how long the game is played for and which paintings take longest, and for nothing else. The counting stops the moment the app goes to the background, so time spent in other apps is never reported at all.

The identifier

The messages are filed under sixteen random bytes that the app generates on its own device the first time it runs and then keeps. It is not derived from anything about you or about your device, it is not an advertising identifier, it is given to no one, and neither I nor anybody else can connect it to a person. Deleting the app deletes it, and what it named is then unreachable for ever.

What is not sent

No name, email address, account, phone number, postal address, contacts, photos, advertising identifier, device identifier, push token or location. There is no chat and nothing you can type into the game, no in-app purchase, no advertising and no notifications of any kind. The messages are stored without an IP address beside them and are not linked to one.

None of this is used to track you across other companies' apps or websites, which is not possible with what is sent even if it were wanted.

Data the app keeps on your device

Three small files in the app's own private storage: how many paintings you have restored, whether music and sound are switched on, and the random identifier above. A message that could not be sent — on a plane, or with the network off — waits in a fourth until it can be. None of these are readable by other apps, and all of them go when you delete the app. Progress lives only there: there is no cloud save and no way to carry a gallery to another phone.

Playing offline

Everything in the game — all forty-three paintings, the art, the music and the rest — ships inside the app. Nothing ever waits for the server, and every feature works with the network switched off for ever. Messages that cannot be sent are simply held and sent later, or dropped.

Children

The game is suitable for all ages. Nothing it collects identifies anyone, so nothing it collects identifies a child either, and there is nothing in it directed at children in particular.

The App Store

The app is distributed through Apple's App Store. Apple may collect information about downloads and, if you have chosen to share it, crash and usage statistics. That happens between you and Apple and is covered by Apple's Privacy Policy. Anything Apple passes on to me arrives as anonymous aggregate figures that cannot identify anyone.

If you write to me

The support page on this website has a form on it. If you use it, the message you write and the email address you give are stored so that the message can be answered, and they are used for nothing else — no mailing list, and nothing passed to anyone. Your IP address is not recorded. Ask and the message will be deleted.

Your rights

Apart from a message you choose to send, there is nothing here that identifies you, so there is nothing that can be looked up, corrected or handed back on request — a copy of the data about you would be a list of timestamps under a random number that nobody can tie to you. If you would rather it were not collected at all, deleting the app stops it and orphans what was sent.

Changes

If this policy ever changes, the new version will be published on this page with a new date at the top.