It probably annoys you when people pick up your Android phone and fiddle with it; but beyond irritation, it's also a potential security risk. For one thing, your privacy could be compromised. For another, your phone's settings could be changed, accidentally or deliberately. A simple app has an equally simple solution: password protection for only those apps you want to protect. That's what Power Apps Tools' Applock Master does. You set a password or locking pattern, and Applock Master keeps protected apps from opening until you enter your password or remove them from the locked list. Applock Master is free and supports Android 2.3 and higher, including the latest versions.
Applock Master's refreshingly simple and ad-free interface opened after we'd completed the setup process, which involves choosing either password or pattern locking. We started with a password, which includes the usual security questions for recovering lost or forgotten passwords. Incidentally, Applock Master doesn't use actual passwords but four-digit number codes instead. For a free Android app, Applock Master has lots of useful settings, including a customizable delay time, anti-uninstall, pattern tracking, unlock vibration, and password and security question maintenance. The only suggestion we'd make is to change the password recovery button's label from "Forget password" to "Forget password?" to make it more immediately clear what the button does.
Applock Master is easy to use: To add an app such as your phone, contacts, photos, or software, simply tap it in Applock Master's Unlocked Apps list. To unlock a locked app, simply press it in the Locked Apps list. We opened the Unlocked Apps list and tapped our Camera, which disappeared from the list and showed up on the Locked Apps list. When we tried to open the Camera, Applock Master's password screen appeared. We tapped in our code, and our Camera opened immediately. No need to add or remove the app from the list: Locking or unlocking it does that for you. Applock Master is an awesome little app that handles a big job with ease.