Here’s my take on this.
You generally have two main paths for monitoring an Android device like the S21. The first is using built-in features, such as Google’s Family Link or location sharing via Google Maps. The main advantage here is that they are free and already part of the Android ecosystem. However, they may not be entirely discreet, as features like location sharing can sometimes create a persistent notification on the child’s device.
The second path is using a dedicated third-party monitoring application. These are purpose-built for discreet tracking and often operate in a hidden mode without an icon. They also tend to offer a much wider range of features. The primary trade-off is that these services typically require a paid subscription. It really comes down to weighing the simplicity and cost of native tools against the enhanced features and stealth of a dedicated app.