Hexlock - Security app locker keeps apps private with smart profiles for any situation

Photok - A safe place for your photos. It stores your photos encrypted on your device and hides them from others.

App Lock and Gallery Vault - Wish you could simply lock all your private apps on your smartphone with just a click?

Google Photos - All your photos are backed up safely, organized and labeled automatically, so you can find them fast, and share them how you like.

AppLock (FOSS) - A privacy App lock FOSS application.

Hide Secrets - Hide Secrets is an app that allows hiding everything they deem confidential on their smartphone.