Privacy policy

Last updated 6 October 2026

Who we are

Sling Theory (com.mani.slingtheory) is a turn-based artillery game for Android, published on Google Play by A Byte of Everything (Mads Kristensen). In this policy, "we" and "us" mean the developer.

For anything about your data or this policy, email appsbyabyteofeverything@gmail.com.

In short

Sling Theory has no ads, and we have added no analytics or crash-reporting software to it. You can play without giving us any personal data: your progress is saved on your phone.

From version 4.47 on there is an optional cloud save. Only if you choose to sign in with Google do we keep your Google account's sign-in details and a copy of your game progress, so that you can carry the progress to another device. You can delete both at any time, in the app or by email.

Google Play Billing, which handles the optional purchase, sends Google its own diagnostic information.

What stays on your phone

Your progress (the campaign, flux, unlocked weapons and skins, slime upgrades, records) and your settings are saved on your phone, in the app's own storage. Unless you use the cloud save, your progress never leaves your phone and we cannot see it. Your settings and the purchase record on the phone never leave it.

Clearing the app's storage in Android settings (usually Settings, Apps, Sling Theory, Storage, Clear data; the names vary by phone) or uninstalling the app removes everything the app keeps on your device. It does not delete a cloud save: see below.

The optional cloud save (version 4.47 and later)

The cloud save is off until you open Settings, Cloud save in the app and tap Sign in with Google. Nothing is sent before that.

When you sign in, Google's sign-in gives us, through Firebase Authentication, a user ID for you and your Google account's email address, name and profile picture link, together with the technical details Google needs to run the sign-in, such as when you signed in. The app only uses the user ID, to find your cloud save, and shows your email address (partly hidden) so that you can see which account you use.

When you tap Upload this device, the app stores one copy of your game progress in Cloud Firestore: the campaign, flux, unlocks, skins, slime upgrades, records and similar game data, a random ID of the phone that uploaded it, the app version and the time. It does not include your settings or the purchase: The Singularity is only ever restored through Google Play. Each upload replaces the previous copy. Download cloud copy replaces the progress on your phone with that copy.

We use this data only to keep and return your cloud save. The legal basis is that you ask for the service (GDPR article 6(1)(b)). Only you can read or change your cloud save: the database refuses everyone else, and every connection is encrypted.

Firebase Authentication and Cloud Firestore are services of Google, which processes this data for us under the Firebase Data Processing and Security Terms. Your cloud save is stored in the European Union (Google's multi-region Europe location for Cloud Firestore). The sign-in service may process the sign-in details outside the European Union, under the safeguards Google provides for that (the EU Standard Contractual Clauses). Google's own handling is described in Google's Privacy Policy.

We keep your sign-in details and your cloud save until you delete them. Signing out keeps the cloud save.

Deleting your cloud save and sign-in

In the app: Settings, Cloud save, Delete cloud save & sign-in. This deletes your cloud save and your sign-in account at once; the progress on your phone stays.

Without the app: email appsbyabyteofeverything@gmail.com from, or naming, the Google account you signed in with, and we delete both within one month. The steps are also on Delete your Sling Theory account.

The optional purchase

The Singularity is an optional one-time purchase processed by Google Play Billing. Google handles the payment, and we never receive your card or other payment details. The app remembers the purchase on your device, and Google Play keeps its own record of it under your Google account, which is how the app's Restore finds it again.

Google Play gives us a record of each order, with details such as the order number, the product and the time, but never your card or other payment details. We keep these records to track sales and refunds. Google handles purchase data under Google's Privacy Policy.

Google Play Billing, the Google library inside the app that handles the purchase, also sends Google diagnostic information about how it works, for example whether a request to Google Play succeeded and connection problems. Google uses it to keep Play Billing working and to support errors. We do not receive it.

Connections

The game's own code makes no network request, except the optional cloud save after you sign in (Google's Firebase services). Its typeface ships inside the app. The other connections are Google Play's own: when you buy or restore The Singularity, Google Play Billing's diagnostic information, and the Google Play Store, when you tap Rate this game.

Up to version 4.44, the app loaded its typeface (Chakra Petch) from Google Fonts when it started with a connection, so Google's servers saw your phone's IP address, as with any website that uses Google Fonts.

Help and feedback

If you email us, we receive your email address and what you write, and we use them only to answer you. An email started from Help & feedback in the app's Settings is pre-filled with the app version, your phone model, Android version and WebView version. You can edit or remove them before sending.

The Discord row in Help & feedback opens a page on this website, which leads to Sling Theory's channel on Discord, an external service run by Discord Inc. under its own privacy policy. The app sends Discord nothing.

Children

Sling Theory is not directed at children. Without the optional sign-in it collects no personal information from anyone.

Your rights

If you use the cloud save, we hold your sign-in details and your cloud save until you delete them. If you have emailed us or bought The Singularity, we hold your email and our order records. Under data protection law (the GDPR) you can ask us for a copy of the personal data we hold about you, and ask us to correct it, delete it, restrict or object to how we use it, or give it to you in a machine-readable format. Email appsbyabyteofeverything@gmail.com to use any of these rights; we answer within one month. You can also complain to the Danish Data Protection Agency (Datatilsynet) or to the data protection authority where you live.

We do not sell your personal information.

Changes to this policy

If the way Sling Theory handles data changes, we will update this page and the "Last updated" date at the top. On 6 October 2026 we added the optional cloud save (version 4.47) and the Google Play Billing diagnostics.

Contact

Questions about this policy or about the app: email appsbyabyteofeverything@gmail.com.