To optimize mobile app performance for handling data encryption or secure storage of sensitive information, there are several key steps you can take. Firstly, consider using hardware-based encryption, such as the Advanced Encryption Standard (AES), which utilizes the device’s built-in encryption capabilities. Additionally, you can optimize your code by minimizing the amount of data being encrypted or decrypted, and by utilizing efficient encryption algorithms. It is also important to properly manage encryption keys and securely store them. Implementing secure storage mechanisms, such as secure databases or encrypted file systems, is crucial for protecting sensitive information. Lastly, regularly test your app for vulnerabilities and stay updated with security best practices to ensure optimal performance and data protection.