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To prevent a child from installing a mobile casino or betting service before the age of 18, app stores and built-in OS tools implement several levels of control.

1. Age ratings and store requirements

1. App Store (iOS)

All apps with gambling features are rated 17 +.
To download, you need an Apple ID created by a user over 18 years old: the first time you set up, the system asks for your date of birth.
Without a valid account ≥ 18 years old, the "Get" button is inactive.

2. Google Play (Android)

Content identification via IARC: Gambling is rated "Mature 17 +" or higher.
In the Google Play settings, you can block content with a rating higher than the specified one (for example, "up to 12 +" or "up to 15 +").
For a user below the established rating, installation is prohibited at the server level.

2. OS Parental Controls

1. Apple Screen Time и Family Sharing

Ask to Buy: the child asks the parent for permission to install any application, including "17 +."
Content & Privacy Restrictions: In Screen Time, you can turn off the installation of applications completely or set hard age filters.
Downtime: prohibit working in the App Store at specified hours, excluding emergency calls.

2. Google Family Link

App claim: All downloads from Google Play require real-time approval from the parent.
Content filters: setting the maximum rating "up to 13 +," "up to 16 +" or "up to 18 +."
Time limits: Limit the daily usage time of the Store app.

3. Block payments and in-game purchases

1. App Store

By default, Password Settings is asking for a password or Face/Touch ID for each purchase.
In the Screen Time settings, you can completely disable in-app purchases.

2. Google Play

In "Settings" you can require a PIN-code for each purchase.
Blocking Google Wallet for unconfirmed accounts - not a single transaction will pass without payment.

4. Additional measures in gambling applications

1. Built-in age-gate

At the first start, you are required to enter the date of birth; without the correct date further neither registration nor deposit.
2. Pre-Bid Check

Request documents (passport, driver's license) through DVS-API or third-party KYC services.
3. Self-exclusion

The option to instantly self-lock the application for a period of 24 h-life through the BetStop national registry.

5. Recommendations to developers and operators

1. Strict compliance with the App Store and Google Play

Make sure that the correct "Gambling" categories and age ratings are indicated in the manifest.
Do not provide links to mobile gambling services outside of app stores.

2. Integration with parental control systems

Process the Screen Time and Family Link APIs to stop working when a lock is detected.
Provide a "guest mode" without access to real bets for players up to 18.

Result

The combination of App Store/Google Play age ratings, iOS and Android parental controls, payment blocking and built-in KYC/age-gate provides multi-level protection for minors from downloading and using mobile gambling applications.