Samsung
Auto-Lock Secure Folder Settings auf Samsung
On most Samsung phones, Secure Folder locks automatically only when the display turns off. Until then, anyone holding the unlocked phone can open it without extra authentication.
This behavior comes from a dedicated auto-lock setting inside Secure Folder itself, separate from your regular screen lock timeout. You can change it to lock the folder immediately after you leave it, every time the device restarts, or after it has been idle for a set period.
Where to change it
Open the path below to see the available options: Tap on Secure Folder ➔ Open the Menu ➔ Tap on Settings ➔ Tap on Auto lock Secure Folder ➔ Choose an option.
Pick Immediately if you want the folder to require authentication the moment you switch to another app. Pick On restart if you mainly worry about the phone being rebooted by someone else. A timed option is useful if you go in and out of Secure Folder frequently and do not want to re-authenticate every few seconds.
If your main concern is battery drain or lock screen delay in general, adjusting the regular screen timeout is a separate setting and will not affect Secure Folder on its own.