Coming in 8.4. An optional biometric lock you can turn on from Profile → Settings → App Lock. When enabled, the app prompts for Face ID or Touch ID on launch and any time you return from the background.
Useful if your phone is sometimes handed to family or kids — your lab results, body composition photos, and personal logs stay protected even when the phone itself is already unlocked. Falls back to your device passcode if biometrics fail.
Off by default. No data leaves your device — the check is purely local.