I've spent a lot of time trying to find the perfect batch image editing tool. I often find that I have to resize images in bulk, Image Smith, by Koingo Software, was the only app that produced great looking results and had a simple, intuitive interface.
It's perfect for what it is. There isn't a single thing I would change.
Image Smith is a powerful batch image processing tool. With a variety of features you can easily scale, reorient, recolorize, convert, and flatten images. Image Smith can open numerous different picture file types, and output in the most common industry standard formats like JPEG, GIF, and PNG.
Use the numerous predefined presets in Image Smith to scale or stretch images down to formats suitable for web banners, e-mailing photos, backups, and more! This is ideal for taking large photos from your camera, which may be upwards of five megabytes each, and scaling and converting them down to a manageable size of only a few hundred kilobytes.