Just a CRUD tutorial for DynamoDB but based on a scenario that makes sense and demoing the API with two languages (Objective-C and Java):
The sample mobile application described here demonstrates how to store user preferences in Amazon DynamoDB. Because more and more people are using multiple mobile devices, connecting these devices to the cloud and storing user preferences in the cloud enables developers to provide a more uniform cross-device experience for their users.
This article shows sample code for both the iOS and Android platforms.
Original title and link: NoSQL tutorials: Storing User Preference in Amazon DynamoDB using the Mobile SDKs ( ©myNoSQL)