Easy Image Morph is a fast and free application to morph two images together.
You can select from 10 different morphing algorithms and adjust the morph weighting per photo. You may also save your morphed image out to a new file.
This is handy for creating composite images, smoothing out blurry images, getting a higher quality image from multiple composite shots, generating change maps for terrain, computer vision research, etc.
You can download Easy Image Morph from the Android Market here.
Update 4/2012 This is now open source and hosted on GitHub. Check it out at my GitHub page.