Privacy Policy

Information we collect

None automatically. The Zperiod app does not collect, sell or share personal information, and it works offline. The one exception is a suggestion that you write and send yourself, described under Sharing and suggestions.

What stays on your device

To remember how you like to use the app, Zperiod saves a few things locally on your iPhone or iPad:

• display preferences, such as how the periodic table is coloured and how element pages are arranged
• which introduction tips you have already seen
• formulas you recently entered in Molar Mass and Reaction Predictor
• your progress in the Play games, such as stars earned and element cards collected
• whether you have Zperiod Pro, and when a Pro subscription renews, as last confirmed by the App Store, so Pro keeps working offline

This information stays on your device. You can clear recent formulas in the app at any time, and deleting the app removes all of it. If you use iCloud device backups, it may be included in your backup by Apple.

If iCloud is turned on for Zperiod, the way you arranged element pages and the level of detail you chose are also kept in sync between your own devices through your iCloud account, using Apple's iCloud key-value storage. This copy is stored by Apple in your iCloud account; we cannot see it. You can turn this off in Settings > [your name] > iCloud.

The Home Screen widgets show information that is built into the app. They do not send anything anywhere.

Purchases

Zperiod Pro is sold through the App Store in two ways: a yearly subscription with a free trial for new subscribers, and a one-time lifetime purchase. Both, the optional tip jar and redemption codes are handled entirely by Apple. We never see your name, Apple ID or payment details; Apple only tells the app whether you have Pro and, for the subscription, when the current period ends. You manage or cancel a subscription in Settings > [your name] > Subscriptions. Apple's own privacy policy covers the purchase itself.

Tracking and advertising

Zperiod shows no ads and does not track you across apps or websites. It contains no analytics, advertising, crash-reporting or social media SDKs.

Sharing and suggestions

When you share an element poster, iOS shows its standard share sheet and the image goes only where you choose to send it.

If you tap Send a suggestion and submit it, the app sends the text you wrote to our feedback service, which forwards it to a private channel on Discord that only the Zperiod team can read. Along with your message we receive the topic you picked, your app language, and a random identifier the app generates on your device. It is not linked to your name, Apple ID or any account, and you can reset it by deleting the app. To limit spam, our service briefly uses a one-way hash of your IP address to count how often suggestions are sent; the IP address itself is not stored or forwarded.

Please do not include personal information in a suggestion. We use what you send only to reply and to improve Zperiod, and you can ask us to delete it by emailing the address below. Discord processes the message under its own privacy policy.

Links to the web

Some pages link to outside sources, such as scientific references. These open in your browser and are covered by those websites’ own policies. This policy covers the Zperiod app only; the zperiod.app website is a separate service.

Children

Zperiod is made for students, including children under 13. Because the app collects no personal information from anyone, it collects none from children either.

Changes to this policy

If this policy changes, we will update it on this page and change the date at the top.

Contact

Questions about privacy? Email [email protected].