As the digital landscape continues to evolve, mobile applications have emerged as a game-changer in the way we conduct our daily lives. From social media platforms to banking services, mobile apps have revolutionized the way we interact with the world around us, providing unprecedented convenience and accessibility at our fingertips. The impact of mobile apps is evident in the staggering statistics, with users now spending an average of five hours per day on mobile apps.
This shift towards mobile-first has created new opportunities for businesses to connect with their customers and improve engagement, underscoring the importance of investing in mobile app development as a key aspect of any successful business strategy. As such, companies that fail to embrace the power of mobile apps risk being left behind in a rapidly changing digital landscape.
With the appearance of cross-platform frameworks like Flutter, building mobile apps has become easier and faster. Flutter is an open-source mobile app development framework that allows developers to build high-performative and high-quality apps for both Android and iOS platforms. In recent years, Flutter (12.64%) has slightly overcome another cross-platform tool as React Native (12. 57%), in terms of most popular technologies.
The rapid popularity of mobile apps brought new challenges for developers, particularly in ensuring the security of users’ sensitive data. So, before delivering your apps to the end customers, app security and users’ privacy should be the top priority.
In this overview, we will discuss the number of steps that can be taken to enhance the security of your mobile apps built with Flutter and explore various tools and techniques for achieving this goal.
Common Security Threats to Mobile Apps
Poorly secured mobile applications can be subject to a broad range of malicious activities, putting users’ private data and information at risk.
Below, we have listed the most prevalent security threats for mobile applications:
- Insecure communication
The lack of secure communication between the app and the server poses a significant threat. If you are not using secure connection protocols, attackers may intercept and access sensitive information, which can put users’ security and privacy at risk.
- Authentication/Authorization Issues
Authentication and authorization are two of the most important aspects of mobile app security. If each of these systems fails, it becomes simpler for unauthorized users to obtain access to sensitive data or app functionality.
- Reverse Engineering
Reverse engineering is the process of analyzing a software application’s code to determine how it works and what it accomplishes. While reverse engineering isn’t always a security risk, it may be used to identify vulnerabilities or flaws in mobile applications that attackers can exploit.
- Lack of API Security
APIs are essential in mobile app development because they enable different software components to connect. Attackers may get unauthorized access to sensitive data, modify the app’s functionality, or execute malicious code if API security is not implemented.
- Unsecured Third-Party Components
Third-party components are code fragments from other sources that are employed in the creation of an app. If not adequately protected, these components can create various security problems. A third-party component, for example, may have access to sensitive data or permit dangerous malware to operate on the device.
- Insecure Cryptography
Encryption is a crucial component of mobile app security that aims to protect sensitive data and communication. However, if encryption is not implemented properly, it can expose the application to serious security risks.
12 Tips to Secure Your Flutter Apps for Mobile
Ensure secure connection
One of the most important things you can do to secure your Flutter app is to use a secure connection. It is crucial as it encrypts all the data transmitted between your app and the server using one or more security protocols. The most commonly used is the TLS protocol (a recent version of the SSL protocol).
Implement Authentication and Authorization mechanisms
Authentication and Authorization are essential security mechanisms. Authentication ensures that only authorized users can access your app, while authorization determines the actions they can perform. When it comes to user authentication in Flutter, you may think of using Firebase Auth or Auth0 SDKs.
In addition to implementing strong authentication and authorization mechanisms, it is also a good idea to consider adding two-factor authentication (2FA). With 2FA, users are required to provide a second form of authentication, such as a code sent via SMS or email. This adds an extra layer of security to prevent unauthorized access to your app.
Secure sensitive user data
Securing sensitive user data is another essential aspect of building a secure Flutter app. It is important to avoid storing sensitive data locally on device memory if possible. However, if you have to do so, consider using tools with built-in data encryption, such as Flutter Secure Storage, Hive, or Isar.
By taking steps to secure sensitive user data, you can help ensure that your app is not only secure but also compliant with data protection regulations such as GDPR and CCPA.
Employ code obfuscation
To make it more difficult for attackers to reverse engineer your app’s binary, consider obfuscating the code. This involves altering your code to make it harder for attackers to understand the underlying data and logic.
Establish your app’s integrity
Consider using Firebase AppCheck. Firebase AppCheck works by providing a secure token to your app, which can be used to verify that requests to your API resources are coming from a genuine instance of your app. Using this tool can help you prevent such common attacks as spam or DDoS attack. It’s worth noting that the Flutter package is still in beta, so you may encounter some challenges with configuring it.
Secure your app’s secrets
Securing your apps’ secrets such as API keys is another step that needs to be taken to enhance your app security. There are several ways to do so. Just remember to never hard-code your secrets in the code and don’t ever track them with the version control system.
Prevent snapshotting in background mode
When a user minimizes your app, most mobile operating systems take a snapshot of the app’s current screen to display in the app switcher. This snapshot can inadvertently expose sensitive information to other users or apps. To prevent this, detect when your app enters the background and add code to either blur or hide sensitive content before the snapshot is taken. In Flutter, you can use the WidgetsBindingObserver mixin to track the lifecycle state of your app and respond accordingly.
Implement local authentication
Local authentication techniques like fingerprint scanning or face recognition offer a more convenient and secure way for users to authenticate themselves. Flutter’s local_auth plugin enables you to leverage these biometric authentication methods in your app.
Prevent usage on jailbroken and rooted devices
Jailbroken or rooted devices are more susceptible to security threats because they bypass the built-in security mechanisms of the operating system. To prevent your app from running on such devices, use a plugin like flutter_jailbreak_detection to detect the device’s security status. If the plugin detects a compromised device, you can choose to either show a warning or restrict the app’s functionality.
Handle permissions explicitly
To ensure user privacy and avoid unnecessary permission requests, request only the permissions your app needs and provide clear explanations for their usage. Use the permission_handler package to handle runtime permissions on both Android and iOS.
Runtime Application Self-Protection (RASP)
RASP solutions are designed to protect your app by monitoring its behavior during execution and detecting malicious activities. Integrating a RASP solution, such as the freerasp package, into your Flutter app can help you respond proactively to potential threats. By implementing RASP, you can monitor your app’s output and react accordingly to detected threats, alerting users or blocking specific actions based on the risk level. This extra layer of security ensures that your app is protected against malicious activities even while it’s running.
Always stay up to date
Ensuring your app remains secure requires staying current with the latest security patches provided by the Flutter team and following best practices in the field:
- Be cautious when integrating third-party libraries, as they might introduce security vulnerabilities that are beyond your control.
- Make it a habit to update your dependencies regularly to minimize potential risks.
- Keep an eye on Flutter-related newsletters, forums, and updates, and conduct periodic security audits to identify and address vulnerabilities in your app.
In conclusion, securing your Flutter app requires careful planning and implementation of various security measures. By following the steps outlined in this article, you’ll be better prepared to protect your app, users, and their data from potential threats.
Stay tuned for the following articles, where we will delve deeper into these steps and provide practical examples and code snippets to help you implement these security measures in your Flutter app.