TinyJPG - Compress JPEG images with perfect quality and file size
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.
ImageResizer - Free online app to crop and resize images
Batch Image Resizer - Resize, crop, shrink, flip, exif-rotate, convert, enhance, process multiple pictures and photos with professional software! 120+ Actions, 30+ Image Formats
Big Photo - Overcome the image resolution limit on iOS devices
ImBatch - ImBatch is a batch image processor with a nice graphical user interface.