Creating a Keychain item is a starting point. Accessibility, sharing and cleanup at sign-out determine its actual protection behavior. Secret management on iOS covers the entire lifecycle.
Evaluation approach
Assess device locking, backup and cross-application access together. Separate data that must stay on one device from data that needs to be portable.
Application example
When storing a refresh token, identify the access required while the device is locked and the application is in the background.
Limits and considerations
Writing to Keychain does not establish that the data can never appear in application memory or logs.
Match access conditions to the data
Assess a Keychain item against its accessibility and access-control conditions. Data needed for background work may require a different choice from a signing operation that demands user presence. Misstated requirements can turn a security improvement into lost functionality.
Test account and local-record behavior through deletion, reinstallation and device replacement. Securely storing a key does not prove that requests made with it are correctly authorized on the server. Storage and use are separate control areas.
Checks and decisions
- Select an accessibility class
- Restrict sharing groups
- Test sign-out cleanup
Inventory which components and accounts can use each secret.
Sources
The primary references above provide the technical basis. Example workflows and evaluation suggestions are this publication’s explanations, not independent test results for a particular product.