Tony Bruno Bologna- Full Stack ArchitectI use Raindrop chrome extension, and they have a mac app as well. Maybe a little bit overkill on what you're looking for, also there's Google Bookmark manager if you want an even simpler approach to image bookmarking, not entirely saving images, but just bookmarking.
Chevy- Audiovisual and Multimedia CommunicatorHands down the best bookmark manager around. It is available on every single platform, including web browser extensions. It's also visually attractive, with a lot of tools and it's free! You can choose to pay for additional tools though.
AddictiveTipsIt's very difficult to imagine a world without bookmarks. Besides the built-in bookmark option in you web browser, there is a whole variety of services, such as Delicious, Pocket and Keeeb, that let you bookmark images, videos and other awesome things you find online.
Cult of MacRaindrop.io is a new bookmarking service for Mac and iOS, and the web, and Android. It lets you save your bookmarks into folders, known as Groups, and those bookmarks are then available from anywhere. The main selling point of Raindrop.io seems to be the slick interface, and the myriad beautiful ways you can arrange the bookmarks therein.
NDTV Gadgets360.comRaindrop.io is a beautiful, powerful - but also slightly confusing - bookmark manager. Most of us probably use the built-in bookmarks mangers on our browsers, but they are fairly limiting. For starters, even if you sync them across devices, your bookmarks are not accessible outside the browser.