It is technically feasible to modify the source code of a mobile application to achieve real-time monitoring of user behavior, but it involves serious legal and ethical issues. Here are some key points to help you understand the complexity and potential consequences of this behavior： ### Technical feasibility 1. **Source code modification**: If you have the source code of the application and have the corresponding programming skills, you can modify the code to add monitoring functions. This may include recording user clicks, inputs, location data, device information, etc. 2. **Data collection**: The modified application can send the collected data to a remote server for your analysis or storage. 3. **Concealment**: In order to keep the monitoring behavior from being noticed by users, you may try to hide the monitoring function so that it runs in the background without attracting attention. ### Legal and ethical issues 1. **Privacy**: Monitoring the behavior of users without their consent is a violation of privacy. Most countries and regions have strict laws to protect user privacy, and unauthorized monitoring may constitute an offense. 2. **Legal consequences**: If you modify and distribute the application without authorization, you may face legal proceedings, including but not limited to invasion of privacy, infringement of intellectual property rights, etc. 3. **Ethical responsibility**: As a developer, you are responsible for respecting the privacy and rights of users. It is unethical to abuse technical capabilities for monitoring. ### Legal way 1. **User consent**: If you do need to collect user behavior data, you must clearly inform the user and obtain their consent. Usually, this requires a clear privacy policy to be provided in the application and explicit authorization from the user. 2. **Transparency**: Ensure that users understand which data is collected, how it is used, and the details of data storage and processing. 3. **Compliance**: Comply with relevant laws and regulations, such as the "General Data Protection Regulation" (General Data Protection Regulation), "California Consumer Privacy Act" (CCPA), etc. ### Summary Although it is technically possible to monitor user behavior by modifying the source code of the application, this behavior involves serious legal and ethical issues. Monitoring without the user's consent is illegal and may have serious legal consequences. If you have a legitimate need to collect user data, you must do so in a transparent and compliant manner, and respect the privacy and rights of users. If you have any questions or need further legal advice, it is recommended to consult a professional lawyer or an expert in related fields.