Movavi Photo Manager - Focus on the memories, forget about managing photos
KeepSafe - Keep your entire photo library safely stored in an encrypted private cloud.
Photos on macOS - Photos keeps your images organized and accessible. Rediscover favorite shots with Memories. Access them on your devices with iCloud Photos.
AppLock (FOSS) - A privacy App lock FOSS application.
XnView MP - XnView is a free software that allows you to view, resize and edit your images. It supports more than 500 different formats!
Hexlock - Security app locker keeps apps private with smart profiles for any situation