Best Security Practices to Fortify Your Cross-Platform Mobile App

Can you recall any industry that has yet to explore the power of digitalization? From banking and shopping to communication and entertainment, mobile apps are actively revolutionizing how businesses and customers interact with each other.

However, with the increasing reliance on mobile apps, the risk related to security threats is highly increasing. Cybersecurity attackers are constantly evolving their techniques to do maximum damage to the apps running on diverse platforms.

This is why applying security in cross-platform mobile apps is vital to maintaining the trust of users, reducing development time and costs, and ensuring a consistent user experience.

Understanding Security in Cross-Platform Mobile Apps

When we refer to security in cross-platform mobile app development, we are talking about the range of practices and techniques that can protect the app from malicious attacks and safeguard user data. The security measures taken must be adaptable to not only present threats but also future threats.

If you are wondering about the common security vulnerabilities that might affect your cross-platform app, then here are some of them.

Common Security Vulnerabilities

• Data breaches: Unauthorized access to sensitive information, including personal user data, financial information, or business data.
• Unsecured Data Storage: Storing sensitive data in plain text or using storage options that do not provide enough protection against unauthorized access.
• Insecure Communication: communicating with remote servers to exchange data that can be intercepted by attackers easily.
• Code Injection: Unauthorized actions and data breaches due to the insecure loopholes in the mobile app.

Best Security Practices for Cross-Platform Mobile Apps

When it comes to security in cross-platform mobile apps, there are a bunch of best practices that can address modern security vulnerabilities. Here are the essential security measures your app should have.

Secure Development Practices (when your app is in the development phase)

• Ensure all user inputs are validated and sanitized to prevent injection attacks, such as SQL injection or cross-site scripting (XSS).
• Use the built-in validation libraries provided by the framework and avoid relying solely on client-side validation.
• Store sensitive data securely using encryption. On Android, use EncryptedSharedPreferences, and on iOS, use Keychain Services.
• Avoid storing sensitive data in plaintext or using insecure storage mechanisms, such as local files or unencrypted databases.
• Never hard-code sensitive information like API keys, credentials, or cryptographic keys in the codebase. Use secure storage solutions to manage these secrets.
• Consider using environment variables or secure vault services to manage sensitive information.

Data Encryption (specific data-related best practices)

• Encrypt sensitive data stored on the device to prevent unauthorized access if the device is compromised.
• Use strong encryption algorithms, such as AES-256, to ensure data is adequately protected.
• Use SSL/TLS to encrypt data transmitted between the app and backend servers.
• Ensure that the app verifies the server’s SSL/TLS certificate to prevent man-in-the-middle (MITM) attacks.
• Regularly update encryption protocols and algorithms to protect against emerging threats.
• Avoid using outdated or weak encryption methods, such as MD5 or SHA-1.

Authentication and Authorization (fortifying the access controls)

• Enhance security by requiring multiple forms of verification, such as something the user knows (password), something the user has (OTP or mobile device, and biometric verification).
• MFA significantly reduces the risk of unauthorized access, even if one authentication factor is compromised.
• Use secure methods to generate, store, and manage authentication tokens.
• Ensure tokens are short-lived and use refresh tokens to maintain user sessions securely.
• Implement RBAC (role-based access control) to ensure users only have access to the resources and actions necessary for their role.
• Regularly review and update roles and permissions to maintain the principle of least privilege.

Network Security (building a secure ecosystem)

• Ensure that APIs are secure and follow best practices, such as using HTTPS and requiring authentication and authorization for all endpoints.
• Implement rate limiting and input validation to protect APIs from abuse and attacks.
• Enforce the use of HTTPS for all network communication to protect data in transit.
• Use strong SSL/TLS configurations and avoid using deprecated protocols and ciphers.
• Implement certificate pinning to ensure the app communicates only with trusted servers.
• Regularly update and rotate certificates to maintain a high level of security.

Secure Third-Party Libraries and Frameworks (keeping the security tight for external interactions)

• Keep all third-party libraries and frameworks up to date to benefit from the latest security patches and improvements.
• Use dependency management tools to track and update dependencies regularly.
• Only use libraries from trusted sources and verify their integrity using checksums or digital signatures.
• Avoid using libraries with known vulnerabilities or that are no longer maintained.
• Limit the use of third-party libraries to those that are essential for the app’s functionality.
• Perform security assessments of third-party libraries before integrating them into the app.

Regular security audits (ensuring the long-term security of the app

• Use static analysis tools to scan the codebase for vulnerabilities and ensure compliance with security best practices.
• Conduct dynamic analysis to identify security issues during runtime and in the app’s operational environment.
• Implement regular code reviews with a focus on security to catch potential vulnerabilities early in the development process.
• Use automated code review tools to complement manual reviews and enhance security coverage.
• Perform regular vulnerability assessments to identify and address security weaknesses in the app and its infrastructure.
• Use both automated tools and manual testing techniques to ensure comprehensive coverage.

Secure App Distribution (ensuring security beyond just securing apps)

• Use code-signing certificates to verify the authenticity and integrity of the app.
• Protect the private keys used for code signing and regularly rotate them to mitigate the risk of compromise.
• Distribute the app through trusted app stores, such as Google Play and the Apple App Store, which implement intense security checks.
• Avoid distributing the app through untrusted third-party app stores that may not enforce strict security measures.
• Use techniques such as code obfuscation, integrity checks, and runtime protection to prevent reverse engineering and tampering.
• Monitor for unauthorized versions of the app and take action to mitigate the risk of the distribution of compromised versions.

If you are an entrepreneur, the above point might be technical, but if you know about them even on a general level, it will help you to discuss better security protocols when you hire mobile app developers.

Platform-Specific Security Practices for Cross-Platform Apps

Although the detailed section we talked about above will help you create a cross-platform app with solid security, let us present some pointers related to specific platforms too (iOS and Android).

iOS Security Essentials

• Utilize Keychain for sensitive data, with access contingent on device security settings.
• Adhere to ATS for network connections; prioritize TLS and limit HTTP exceptions.
• Respect sandbox rules, configure everything precisely, and avoid private APIs.

Android Security Essentials

• Store critical data in encrypted shared preferences with secure key management.
• Use StrictMode in development to identify and resolve performance and security issues.
• Manage cryptographic keys via Keystore, ensuring secure generation and usage.

Key takeaways to fortify your cross-platform app

Soon, it is possible that smartphones could act as computers, where all you have to do is plug them into a monitor and utilize the apps installed on the phone in desktop mode. But when you target this many use cases, you have to keep it fortified with the best security practices for cross-platform mobile apps.

Key takeaways from this blog include a clear understanding of modern security vulnerabilities, robust data, network, and authentication security, and ensuring that a few platforms have specific security considerations.