Requirements: Android OS
Price: $2.55
Overview: What's the best app protector? Strong password? Of course NOT. The best proector would let prier not be aware of any protection. App Locker II is one such protector to protect your private apps.
When launching a protected app, it will throw a fake crash error which may mislead guest user into thinking that your app has a glitch or something, so it can stop guest from using your protected app in a natural manner.
But owner can clear it through several secret ways, also including password protection.

*** NOTE ***
1. New user please buy the 'Invisible Protector' or 'Invisible Protector II'. Iivisible Protector is widget version of App Locker II. There are almost all same except the widget version will not show app icon on the launcher screen which make it even more secret. Invisible Protector II is dialer launch version, even won't show icon in Widget menu and need dial '#999' to launch it.