The evaluation of cryptography usage in Android applications focuses on assessing how effectively cryptographic techniques are implemented to secure sensitive data, such as passwords, personal information, and transaction details. This evaluation includes examining the selection of cryptographic algorithms (e.g., AES, RSA), key management practices, and the proper use of cryptographic libraries such as the Android Keystore system. It also involves identifying potential vulnerabilities such as weak encryption, improper key storage, or insecure data transmission. The goal is to ensure that cryptographic practices align with industry standards and best practices, thereby protecting user data from threats like data breaches, man-in-the-middle attacks, and unauthorized access.