GIMP - GIMP is a multiplatform photo manipulation tool.
Photoscape - high quality photo editing software, that enables you to fix and enhance photos.
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.
XnView MP - XnView is a free software that allows you to view, resize and edit your images. It supports more than 500 different formats!
Pixlr - Pixlr® makes it easy to transform everyday images into stunning works of art.
Fotor - Fotor is an all in one visual platform. It includes photo editor, collage maker, and graphic designer. You are free to make a visual look more beautiful.