Sparklefish is a FREE app which is a story creation app with a difference it is a little like wacky web tales which you use on the computer, however with this app you use your voice and orally record the extra words from the story.
The app is great to use for teaching concepts such as parts of speech, adjectives, verbs etc. It is also great for teaching oral language skills. Students could use this app individually or in pairs to increase conversation and collaboration.
I have created a quick tutorial below: