Abstract: Approaches are described for a client (e.g., an application executing on a computing device) requiring a particular storage format to provide information describing its storage format to a service, such as a multi-tenant computing environment. The service contains data that the client desires to acquire, but in various embodiments, the data on the service is in a different storage format than the format required by the client. The service receives the information describing the storage format and processes the data accordingly, and then provides the processed data to the client in the format required by the client.

Abstract: A service provider network includes a host computer that communicates with a plurality of client devices associated with a user. In order to synchronize the plurality of client devices with respect to content stored within the service provider network, a synchronization service checks to determine if a checkpoint is present within the synchronization service when a request for updated content is received from one of the client devices. If no checkpoint is present in the synchronization service, then content within the user's account may have been updated. If a checkpoint is stored within the synchronization service, then the checkpoint in the synchronization service is compared with a checkpoint in the request. If the checkpoint in the synchronization service is older, content in the user's account has not been updated. If the checkpoint in the request is older, then content in the user's account may have been updated.