HardG 2.5.1 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. This free Mac application was originally produced by Innoveghtive Inc. The program lies within Design & Photo Tools, more precisely Viewers & Editors.
From the developer:
Hard G lets you quickly find and use GIFs in a variety of apps on your Mac. You can use the Search field to find any GIF you like. Whether you're looking to share a reaction, a favorite moment in a show, or just a laugh, this app has what you're looking for. You can use QuickLook to preview the GIF at full size. Sharing your GIF is as easy as drag and drop. If you want to use a GIF again, you can keep it in your Favorites.
You may want to check out more Mac applications, such as Movie2Shot, TVPaint Animation or Cuadro, which might be similar to HardG.