Iconosquare - Schedule now. We'll post on Instagram for you later!
ImBatch - ImBatch is a batch image processor with a nice graphical user interface.
Later - Schedule and manage your Instagram posts
DVDVideoSoft Image Convert and Resize - Free Image Convert and Resize is a compact yet powerful program for batch mode image processing.
Storyheap - Manage your SnapChat and Instagram stories.
Ralpha Image Resizer - High-speed image batch conversion tool