Stereogram app for iPhone and iPad

Stereogram Creator allows you to combine two photos of the same scene, taken from slightly different positions, into a single stereogram.
First you take one photo which will become the left-hand view; then you shift the camera to the right by a couple of centimetres to take another photo, the right-hand view. A semi-transparent overlay helps you with the process.
You will then see the stereogram. One way to see the 3D effect is to go cross-eyed until you see three images, of which the middle one will be the 3D view. Two dots are placed on top of the images to assist with this.
The stereogram can be saved to the camera roll if you want to keep it, otherwise you can dismiss it and take another one.
Note: This app requires a camera.