Photoshop Touch is a photography application developed by Adobe. This application lets you use the various features of Photoshop on a mobile device.
Once you start up Photoshop Touch, you'll get a similar interface like Photoshop on a PC but it will be more usable on a touch-screen device. Photoshop Touch even has unique features that other versions of Photoshop don't have like the Camera Fill function that lets you fill the background of any picture with what you have currently on your camera.
Overall, Photoshop Touch is a worthy version of the program for anyone looking to edit their photos on the go. Some more experienced users will only be concerned about having a smaller screen to do more complicated tasks.