Mobile Data Storage and Persistence Questions

Mobile application storage and data persistence patterns, trade offs, and security considerations across mobile platforms. Topics include small key value stores and preferences, local relational and object databases such as SQLite and platform native frameworks, file system storage and directory types, temporary versus cached versus persistent storage semantics, data lifecycle and retention policies, schema versioning and migration strategies, performance and concurrency considerations, synchronization and backup strategies, and secure storage options and encryption at rest. Also covers platform specific secure storage mechanisms for sensitive data, handling of credentials and tokens, avoiding hard coded secrets, secure data deletion, permission and sandboxing implications, and best practices for protecting user privacy and complying with data protection requirements.