What are the most important mobile app authentication best practices?

2 Implement secure data transmission and storage

When you authenticate users in your mobile app, you need to ensure that the data you transmit and store is secure and encrypted. This means that you should use HTTPS protocol, SSL certificates, and TLS encryption to protect the data in transit, and avoid sending sensitive data such as passwords or tokens in plain text or URL parameters. You should also use secure algorithms and libraries to hash and salt the passwords or tokens before storing them in your app or backend database, and avoid storing them in insecure locations such as local storage, cache, or cookies. Additionally, you should use device-specific encryption keys to encrypt the data at rest, and implement data wiping or remote locking features in case of device loss or theft.

4 Implement multi-factor authentication

Multi-factor authentication (MFA) is a technique that requires users to provide more than one piece of evidence to prove their identity, such as something they know (e.g., password), something they have (e.g., phone), or something they are (e.g., fingerprint). MFA can enhance the security of your mobile app authentication, as it reduces the chances of unauthorized access or account takeover, even if one factor is compromised. MFA can also improve the user experience, as it can reduce the frequency of password prompts or resets, and offer more options for user verification. However, MFA can also introduce some challenges, such as user friction, network dependency, or device compatibility. Therefore, you should implement MFA in a way that is context-aware, adaptive, and user-friendly, and offer users the option to opt-in or opt-out of MFA, depending on their preferences and risk levels.

5 Follow the principle of least privilege

The principle of least privilege is a security best practice that states that users should only have the minimum level of access and permissions that they need to perform their tasks, and nothing more. This principle can help you prevent or limit the damage caused by malicious or accidental actions, such as data breaches, identity theft, or privilege escalation. To follow this principle, you should design your mobile app authentication system in a way that allows you to assign and manage roles and permissions for different users and resources, and enforce them consistently and securely. You should also monitor and audit the user activities and access logs, and revoke or update the access and permissions as needed, based on the user behavior, context, or risk.

6 Test and update your authentication system regularly

Finally, you should test and update your mobile app authentication system regularly, to ensure that it works as intended, and that it meets the latest security standards and best practices. You should perform various types of testing, such as functional, performance, usability, and security testing, to identify and fix any bugs, errors, or vulnerabilities in your authentication system. You should also update your authentication system frequently, to keep up with the changing user expectations, app features, and security threats. You should also inform and educate your users about the updates and changes in your authentication system, and encourage them to use the latest version of your app and the most secure authentication method available.