Downloading Pixbuf 1.1 for Mac from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this app available. The program lies within Design & Photo Tools, more precisely Viewers & Editors. We recommend checking the downloaded files with any free antivirus. The actual developer of this free software for Mac is Pixbuf, s. r. o.
From the developer:
Pixbuf is a better way to share and sell your photos. It offers a simple solution to share your images to all major social networks (Instagram, Facebook, Twitter, Pinterest, Tumblr) and photography services (500px, Flickr, Youpic, DeviantArt) with one click.
You may want to check out more software for Mac, such as Smith Chart for Mac, Movie2Shot or TVPaint Animation, which might be related to Pixbuf.