Effective date: 11 October 2026 · Last updated: 18 October 2026
These Terms govern your use of Marble Trails (“the app”), published by Dragonball Studio (“we”, “our”). By installing or using the app you accept these Terms. If you do not accept them, please do not use the app.
1. Licence
We grant you a personal, non-exclusive, non-transferable, revocable licence to install and use the app on devices you own or control, for your own non-commercial use. You may not copy, modify, reverse-engineer, decompile, rent, resell or redistribute the app or any part of it, except where such restriction is prohibited by applicable law.
2. What the app is
The app is a single-player puzzle game. Constellation Lab uses mirrors, prisms and mixers to route coloured light to stars. Marble Arcade contains marble-shooting puzzles, a rolling-chain campaign and an Endless mode. Fresh iOS installs lead with Lab; fresh Android installs lead with Arcade. Both remain accessible, and returning players open the Home of their last played mode. Lab circuits, undo and hints are free; optional coin purchases apply to Arcade tools, looks and revives.
- There is no online multiplayer, no matchmaking and no chat.
- Boosters appear on the track during play and are free. There is no wagering, no betting, no cash prizes of any kind. Nothing in the app can be exchanged for money or anything of value.
3. Purchases
The app offers optional in-app purchases: coin packs and Remove Ads. Every purchase is made through the Apple App Store or Google Play and is governed by their terms, including their refund policies; we never handle payment. Coins, whether earned or bought, are a licence to use in-game items only: they have no cash value, cannot be transferred, exchanged or redeemed, and are stored only on this device. Reset progress keeps them; Delete my data or uninstalling removes them, including bought coins. Remove Ads is tied to your store account and can be restored with Restore purchases.
4. Advertising
The app is supported by advertising served by Google AdMob. Ads are not shown over the board during play. Remove Ads turns the ads off. Ad content and your choices about personalisation are described in our Privacy Policy.
5. Leaderboards and user-chosen content
To appear on the leaderboards you pick a display name and a country. By doing so you agree that:
- the name and country are publicly visible to other players;
- you will not use a name that is offensive, impersonates another person, promotes illegal activity, or infringes anyone’s rights;
- we may remove or reset any name that breaches the above, without notice.
Names are screened automatically, but automatic screening is imperfect. Report a problem name to nguyenduyanhuit1989@gmail.com.
You can delete your leaderboard rows and all local data at any time from Settings → Delete my data in the app.
6. Acceptable use
You agree not to tamper with the app or its data in order to falsify leaderboard standings, nor to use the app to distribute malware or to interfere with our services or other players.
7. Availability and changes
We may update, change or discontinue the app or any feature of it at any time. Online features (the leaderboards) may be unavailable from time to time; the game remains fully playable offline when they are.
8. Disclaimer of warranties
The app is provided “as is” and “as available”, without warranties of any kind, whether express or implied, including fitness for a particular purpose and non-infringement. We do not warrant that the app will be uninterrupted or error-free.
9. Limitation of liability
To the maximum extent permitted by applicable law, Dragonball Studio is not liable for any indirect, incidental, special or consequential damages, or for loss of data or profits, arising from your use of the app. Nothing in these Terms limits liability that cannot be limited by law, including your statutory rights as a consumer.
10. Intellectual property
The app, its code, artwork, levels, sound and text are owned by Dragonball Studio.
11. Governing law
These Terms are governed by the laws of the Socialist Republic of Vietnam, without regard to conflict-of-law rules, and without prejudice to any mandatory consumer-protection rights you have in your country of residence.
12. Contact
Dragonball Studio — nguyenduyanhuit1989@gmail.com
Apple-specific terms. These Terms are between you and Dragonball Studio only, not with Apple Inc. Apple has no obligation to provide maintenance or support for the app. In the event the app fails to conform to any applicable warranty, you may notify Apple and Apple will refund the purchase price (if any); to the maximum extent permitted by law, Apple has no other warranty obligation with respect to the app. Apple is not responsible for addressing any claims relating to the app, including product-liability claims, any claim that the app fails to conform to a legal or regulatory requirement, and claims arising under consumer-protection or similar legislation. Apple and its subsidiaries are third-party beneficiaries of these Terms and may enforce them against you.