AppLock: FREE Android App can Lock Almost Everything with Password
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The best thing about this AppLock is that it not only prevents people to open your apps, SMS, emails etc. but also prevent others to receive calls. It also prevents others to install & uninstall apps, change settings, lock Google Play store on your Android device.
AppLock provides you two modes to protect your privacy, first, Password Lock, where you can put your desired password and it will ask you while opening AppLock app on your device, and Second, Pattern Lock, where you can set pattern to lock your system settings, SMS, and all othere apps.
While setting your pattern lock, it will then ask you to save your pattern and whenever you open this AppLock it will ask you to put the pattern before entering into settings.
Once you have changed settings to lock or unlock according your needs, close it and reopen, it will again ask you to put PIN if you have set PIN, correct PIN will allow you to unlock app againg.
AppLock Features: Protects any apps using password or pattern.Photo Vault and Video Vault.Customize background, set your favorite photo.Profiles, easy to change the locks.Automatic lock at given time and Location.Random keyboard.Lock switch (WiFi,BT,3G/4G Data…).Widget for quick locking/unlocking.Locks incoming or outgoing calls.Lock system Settings.Lock Google Play Store.Quick lock switcher on status bar.Re-lock policy: allow short exit, no need to unlock again.Prevent apps from being uninstalled.Hide AppLock’s icon from launcher.AppLock can be prevented from being uninstall.AppLock cannot be killed by task killers.Little memory footprint and power-saving
Overall, a great Free app available on Android store which gives you features like premium app, used by millions of people and increasing day by day, do give it a try.