ACDSee - ACDSee is an image viewer that uses very little system resources, and it has a small, sleek size that won't take up much space on your system.
GIMP - GIMP is a multiplatform photo manipulation tool.
Adobe Bridge - Download Adobe Bridge CC digital asset management software when you get started with Adobe Creative Cloud. Start your free trial today.
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.
Sketch - Professional digital design for Mac.
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.