On fotoflexer.com, you can editing software without any software installation. Just upload a photo to its web site, then use the online tool to retouch and enhance your photos via IE.
It's very easy to use and if you are looking for a web site other than a software, I recommend this one.
No software installation
Powerful editing tool like rotate a image, crop a image and lots fo photo effects.
Some functions somhow slow because IE limition and if you like more powerful tool, maybe install a photo editing software would be much better.
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