Method, system, and computer program product for improved synchronization efficiency for mobile devices, including database hashing and caching of web access errors

Methods, systems, apparatuses, and computer program products for improving efficiency in transfer of content to mobile devices are provided. In a first aspect, hashing is used in a synchronization server to determine whether objects have changed, and therefore need to be updated on the mobile device and/or on the mobile device server. For example, databases are hashed on a record-by-record basis. Records determined to be changed are transmitted to the mobile device and/or updated on the synchronization server. In another embodiment, errors occurring during attempts to obtain unavailable web content are cached (i.e., "negative caching"). The cached errors are accessed during subsequent attempts to obtain the unavailable web content to avoid spending time on the subsequent attempts.