Apps with 'Layer manipulation' feature
GIMP is a free program for such photo retouching, image composition and image authoring. Essentially it's the closest thing to Photoshop you can get for free.
Professional, open-source raster graphics editor with advanced digital painting and sketching tools and workflow features.
Paint.net is a free and very capable image editing software for Windows. Great alternative to Photoshop for people that do not need all the stuff PS offers.
Professional image editing software for desktop and iPad.
Adobe Illustrator is a commercial vector graphics editor.
Online photo editor, which can work with PSD, XCF and Sketch files (Photoshop, Gimp and Sketch App). Convert between PSD, XCF, JPG, PNG and many other formats. .
A professional digital drawing and painting application for iPad (and iPhone as a Pocket version).
PaintTool SAI is high quality and lightweight painting software, fully digitizer support, amazing anti-aliased paintings, provide easy and stable operation, this software make...
LazPaint is a free and open image editor, like PaintBrush or Paint.Net, written in Lazarus (Free Pascal). Uses BGRABitmap library. LazPaint has features layers and transparency.
Adobe Photoshop Elements combines power and simplicity so you can make ordinary photos extraordinary; tell engaging stories in beautiful, personalized creations for print and the...
openCanvas, popularly abbreviated as oC, is a popular Japanese image editing program. openCanvas is a paint software package that can be used by experts and novices alike.
Dynamic image processing, hosting and rich-media for retailers and eCommerce. Sirv saves you time by automatically optimizing, resizing and choosing the most optimal format of your images, delivering a unique experience to each of your users.