Hexlock - Security app locker keeps apps private with smart profiles for any situation
App Lock and Gallery Vault - Wish you could simply lock all your private apps on your smartphone with just a click?
AppLock (FOSS) - A privacy App lock FOSS application.
Super AppLock - * Protect installed apps using password or pattern! * Support PIN lock and Pattern lock!
Applocker - You can use AppLocker as part of your overall security strategy for the following scenarios:
KeepSafe - Keep your entire photo library safely stored in an encrypted private cloud.