Quick AppLock Pro locks apps by displaying the lock screen whenever a locked app is launched.
Those who do not know the unlocking pattern will be unable to launch locked apps.
Apps installed on smartphones and tablets often store sensitive personal information such as photos, emails, SNS details, address books, and bank and credit card information.
By putting a lock on apps that handle this information, Quick AppLock Pro protects your privacy.

【Why "Quick" ?】
Many other locking apps have a time lag between the moment a locked app is tapped and when the lock screen appears.
Although this time lag is usually quite short, it is difficult to feel safe because important information can be seen during this time.
As Quick AppLock Pro is designed with the highest priority on getting the lock screen to appear as quickly as possible, it protects your privacy more securely than other locking apps.

✔ Enhanced security against device theft and loss
✔ Protects privacy when lending devices to friends
✔ Partial restrictions can be put in place when devices are used by children
✔ Restricts functions for exhibition devices
✔ Prevents pocket dialing
✔ Prevents others from accepting calls on your phone and does not show caller ID
✔ Prevents others from peeking at emails, data, photos, etc.
✔ Can be made to unlock with fingerprint authentication

【Features】
[Lockable items]
• Apps
• Install/Uninstall
• Incoming call
• Outgoing call
• Settings (Device Settings)
• Recent Apps
• Wi-Fi
• Bluetooth
[Other]
• Change unlock pattern
• Fingerprint unloc
• Touch vibrate
• Make pattern visible
• Security email
• Advanced protection (Protects Quick AppLock Pro from being uninstalled.)
• Re-lock after screen on (When screen is turned off with the locked app open.)
• Auto Unlock when connected to Wi-Fi
• Change themes
• Auto startup on device reboot
• Enable/Disable app widget

You can check this app's features and operations with a free trial.
Please check the features and operations by free trial before you buy.
https://play.google.com/store/apps/details?id=jp.snowlife01.android.applock0