App Locker - Prevent access to app

Developer's DescriptionBy The Simple AppsApp Locker allows you to prevent unwanted access to your apps with PIN, pattern lock.App Locker allows you to prevent unwanted access to your apps with PIN, pattern lock.Please read descriptions below carefully before using this app.Features:Safe and easy to useNo annoying adsNo internet accessNo dangerous permissionsSupport Android 5.1 and upAdvanced security settings:- Prevent uninstalling App Locker by activating its device admin- Prevent turning off App Locker by locking Settings app which can be used to clear app dataPlease note that:This app does not use INTERNET permission, so it is not able to access the internet. Therefore, it cannot connect to a remote server to steal your data. And it only uses the accessibility service to be able to detect if an app is being accessed. So, please feel safe to use!If you have any questions, suggestions or bugs, please contact me at thesimpleapps.dev@gmail.comFAQ:How if I forget the lock screen?Because this app doesn't want to use Internet access (for your privacy), so it doesn't support password recovery via internet such as email.If you forget password, you can clear app data or re-install app.But if you activated the device admin and also locked Settings app, you will no longer be able to clear app data or uninstall app.So please try to not forget the password!Why can't I press "OK" button of the dialog?This problem may be caused by using an app that can overlay other apps, such as blue light filter apps. Those apps may overlay the dialog, so that cannot press "OK" button. This is a bug of Android OS which needs to be fixed by Google via an OS update. So if your device hasn't fixed yet, you may need to turn off the light filter apps and try again.