PhotoPenguin App - PhotoPenguin is a completely free batch photo editor with support for cropping, resizing, adding watermarks, and converting photos to other formats. It works on the user's device, using the capabilities of modern browsers.

FotoFlexer - FotoFlexer is the most powerful online photo editor in existence.

ImBatch - ImBatch is a batch image processor with a nice graphical user interface.

Photoshop.com - Photoshop.

Batch Image Resizer - Resize, crop, shrink, flip, exif-rotate, convert, enhance, process multiple pictures and photos with professional software! 120+ Actions, 30+ Image Formats

piZap - Free online photo editing software.