You can choose a background such as places, animals, landscapes or you can upload your own image. Then simply take a new photo or upload a new photo and follow the simple instructions on how to "Cut" and then "Paste" into your background.
I love how tactile this app is. You can use two fingers to rotate your image.
Free, but it has ads.
$1.99 with no adds.
I created the following example in less than 2 minutes.