Privacy Policy
Duo Worlds is an iPhone app of animated 3D worlds and stereograms. This policy covers the app and this website, duoworld.app.
Controller: Duo Worlds (a trading name), based in the United Kingdom ("we", "us"). Contact: hello@duoworld.app.
In short
- The app collects no personal data. It has no account, no analytics, no advertising and no tracking, and it makes no network connections.
- What you change in the app stays on your iPhone.
- We do not sell data, and we do not track you across other companies' apps or websites.
What stays on your iPhone
- Your saved worlds and stereograms, the music you chose and its volume, the view mode, the Animate previews switch and your answers in the density comparison. They are kept in the app's own storage on your iPhone and are never sent to us. Deleting the app deletes them. Like any app's data, they are included in your iPhone's backup.
- Some screens read your iPhone's motion sensors so the view moves as you tilt the phone. The readings are used on the phone as they arrive and are never stored or sent.
Photos and sharing
- If you save a picture to your photo library from the share sheet, iOS first asks whether Duo Worlds may add photos. The app can add pictures but cannot see your library. You can change this at any time in iOS Settings under Duo Worlds.
- When you share a picture or a collection, it goes where you choose in the share sheet, under that app's or service's own terms. We do not receive it.
Apple
- Apple distributes the app through the App Store and handles any payment. Apple gives us sales figures and App Store statistics that do not identify you.
- If you share analytics with app developers (iOS Settings, Privacy & Security, Analytics & Improvements), Apple sends us crash reports and usage statistics that do not identify you.
This website
duoworld.app is hosted by Vercel, which receives your IP address and browser details when you visit and keeps them in its own logs. Vercel may process them outside the UK, including in the United States. The site sets no cookies, has no analytics or advertising, and loads nothing from other websites.
If you email us
We receive your email address and what you write, and we use them only to reply to you. Your message is stored by our email provider. We keep the conversation for as long as we need it to help you, and delete it when you ask.
Legal bases
Under UK GDPR we rely on legitimate interests to run and protect this website and to answer your emails.
Your rights
You can ask for a copy of the personal data we hold about you, which in practice means emails you sent us, and ask us to correct or delete it or to stop using it. Write to hello@duoworld.app. You can also complain to the UK Information Commissioner's Office at ico.org.uk.
Children
The app collects no personal data from anyone, including children.
Changes
If a new version of the app changes what happens to data, we update this page before that version reaches the App Store and change the date at the top.