I’ve always been irked that iPhone photos can only seemingly be removed from the device by iTunes. The iPhone doesn’t show up like a normal camera device in Finder and you can’t get to it even through navigating with Terminal. Thanks to a post that came up during a little searching, it turns out the Image Capture app on Macs can do exactly that—I don’t know how to do this on a Win PC.
Yup, right in your Applications folder it turns out that there’s the Image Capture app:
If your iOS device is connected up you’ll see it on the left and then you can select any number of images and click the Delete button at the bottom of the window.