How to build a secure mobile app in 2024

With the rise of mobile use worldwide, so are mobile app security issues and threats.

As with web or mobile app development, protecting sensitive data and ensuring robust security is imperative. As security breaches and vulnerabilities continue to rise, developers must incorporate comprehensive mobile app security measures from the outset. 

This blog post explores ten critical strategies for enhancing mobile application security, providing developers with a comprehensive checklist to guard against reverse engineering attacks, data breaches, and other security threats. UK App developers, along with their global US counterparts, play a crucial role in ensuring that mobile applications are both functional and secure, effectively safeguarding user data and maintaining trust on the wider global stage.

Top 10 Tips for Building a Secure Mobile App in 2024

1. Initiate Early Integration of Security Measures

Integrating security considerations at the beginning of the mobile app development process is crucial for creating a secure foundation. This proactive approach ensures that security is not an afterthought but a fundamental aspect of the development workflow. By involving security experts from day one, potential vulnerabilities can be identified and mitigated early, reducing the risk of costly and damaging breaches later on. For instance, security specialists can work alongside developers during the planning stages to incorporate encryption protocols, secure authentication methods, and data protection mechanisms right from the first line of code.

2. Continuously Conduct Testing

Testing is an indispensable part of securing a mobile app. However, simply running a few tests before deployment is insufficient. Continuous testing throughout the development process helps identify and address vulnerabilities before they become serious threats. Developers should adopt a cycle of testing, fixing, and retesting, which is essential to maintaining a secure app over time. Tools like static and dynamic analysis software can automate some of these tests, providing regular feedback on the security status of the app. This ongoing commitment to testing helps ensure that the app remains robust against emerging security threats.

3. Evaluate the Reliability of External Code

The use of third-party libraries and frameworks can accelerate development but also introduces risks if these components are not fully vetted. Developers must exercise caution when incorporating external code into their apps. It’s essential to assess the security posture of these components by reviewing their source, checking for known vulnerabilities, and understanding their maintenance and update policies. Performing a thorough security audit on third-party modules can prevent the introduction of backdoors and other security flaws. When possible, opt for well-maintained and widely trusted libraries that adhere to security best practices.

4. Implement Rigorous API Security Practices

APIs are the backbone of modern mobile applications, facilitating interactions between apps, servers, and databases. However, their exposure to the internet makes them a prime target for attacks. Securing APIs requires implementing rigorous authentication and authorization measures to ensure that only legitimate requests are processed. Techniques such as using HTTPS, adding rate limiting, and employing an API gateway can protect against common threats like man-in-the-middle attacks, data breaches, and denial of service attacks. Developers must also ensure that all API endpoints are well-documented and monitored for unusual activity.

5. Adopt an Attacker’s Perspective in Development

Thinking like an attacker is a valuable strategy in security-centric development. By adopting the mindset of a potential hacker, developers can anticipate and defend against methods that might be used to compromise the app. This involves scrutinizing every component of the application for vulnerabilities that could be exploited, such as weak encryption, insecure data storage, or insufficient input validation. Regular penetration testing, where security experts attempt to exploit system weaknesses, can provide insights into how an attacker might breach app defenses and help developers prioritize security fixes based on real-world attack scenarios.

6. Reduce Security Risks by Limiting App Permissions

Every permission an app requests can potentially open up new attack vectors. It’s crucial for developers to adopt a principle of least privilege, where the app only requests permissions that are absolutely necessary for its functionality. This minimizes the risk of exposing sensitive device capabilities or user data to attackers. For example, if an app doesn’t need to access the camera or location services, it shouldn’t request these permissions. Regular reviews of permissions can also help ensure that any changes in the app’s functionality are reflected in updated permission requests, thereby maintaining security as the app evolves.

7. Consider the Security of Data Stored Locally

Encrypting data stored on devices is crucial for protecting users, and safeguarding sensitive data and information from unauthorized access. Implementing mobile app data encryption should be a standard practice, especially for apps that handle sensitive or personal information. Developers need to employ robust encryption algorithms and manage encryption keys securely to ensure the safety of stored data. This process involves not only selecting strong encryption methods but also implementing them effectively to protect data at rest. Additionally, it’s important to consider the data lifecycle and ensure that encrypted data is securely deleted when no longer needed, preventing any potential recovery of sensitive information after the app’s uninstallation. By prioritizing mobile app data encryption, developers can significantly enhance the security of the information stored within the app, safeguarding it against potential breaches and unauthorized access.

8. Enhance the Security of Data Transmissions

Data in transit is vulnerable to interception and manipulation, making it essential to implement strong encryption protocols such as SSL/TLS for all communications between the app and external servers. Developers should enforce the use of HTTPS to secure all web traffic, and consider additional security measures like certificate pinning to prevent man-in-the-middle attacks. Testing for vulnerabilities in data transmission should be part of the regular security assessments, ensuring that data cannot be read or tampered with during transit.

9. Manage User Sessions with Secure Tokens

Effective session management is crucial to maintaining the security of user information and preventing unauthorized access. Tokens, particularly JSON Web Tokens (JWT), offer a robust method for handling user sessions. They provide a way to securely transmit information between parties as a JSON object that can be verified and trusted due to its digital signature. Tokens can be designed to expire after a certain period or upon logging out, reducing the risk of session hijacking. Developers should implement token-based authentication to enhance security and improve the user experience by facilitating seamless interactions across different components of the app.

10. Incorporate Anti-Tampering Measures in App Design

To guard against the modification and misuse of app code, incorporating anti-tampering mechanisms is essential, especially for apps that operate on open platforms like Android, where apps are easy to decompile and modify. Techniques such as code obfuscation, which makes code difficult to read and understand, and integrity checks, which verify that the app has not been modified since its release, can be effective. Developers should also consider using secure coding practices and tools that detect and prevent tampering attempts to protect both the app and its users.