Perfect AppLock - App Protector is a top-rated application by Morrison Software available on Android. This app allows you to protect any application with a password, pattern, or gesture. It offers a wide range of features for free, including screen filter support, rotation lock support, and fake popup. Additionally, the app provides a watchdog feature that takes a photo of the attacker after the third failed password attempt.

Perfect AppLock - App Protector also allows you to lock Wi-Fi, 3G data, Bluetooth, Sync, USB, outgoing and incoming calls, and app installs and uninstalls. Moreover, it supports time and Wi-Fi-based locking policies. This application uses minimal resources and supports gesture, pin, pattern, and text passwords.

As for permissions, this app requires call permission for the stealth mode feature, SMS permission for remote control, and take picture permission for the watchdog feature. It is worth noting that AppLock service restarting is required after each update, and the phone calls permission is required for stealth mode.

Overall, Perfect AppLock - App Protector is an excellent utility and tool application that provides powerful features to protect your applications and data. It is compatible with AndroidLollipop and uses the Device Administrator permission.