Xamarin.Auth or MSAL: Trade‑off Between Manual Token Refresh and Automatic Cache Persistence for Least‑Privilege Access

When implementing least‑privilege authentication in a Xamarin.Forms app, developers must decide how to handle token expiration and cache persistence across app updates. Xamarin.Auth stores tokens in platform‑specific secure stores and requires manual refresh logic, which can lead to stale tokens if not correctly implemented. MSAL automatically acquires and refreshes tokens using silent authentication and can persist the cache to shared device storage, reducing manual effort but adding setup complexity for redirect URIs and broker integration. The goal is to select the approach that balances security, maintenance overhead, and reliable token availability after an update.

• Which library provides more reliable token persistence across reinstall or update scenarios without additional custom storage code?
• How does the manual refresh requirement of Xamarin.Auth affect the risk of using stale tokens under least‑privilege scopes compared to MSAL’s automatic refresh?
• What trade‑off exists between MSAL’s automatic token acquisition and Xamarin.Auth’s broader protocol flexibility when considering re‑authentication prompts after an app update?