This paper describes the design and implementation of DataX, middleware for enabling remote database access from heterogeneous thin clients. Unlike existing commercial o.erings that require a standalone database on the client side, DataX partially replicates the server database in the form of XML, using a weak consistency criterion. It also adapts data replication to device characteristics and user preferences. It employs a per-device renderer to present data in a form layout, making the data access semantics separate from user interaction details and independent of the device type. It allows for rapid development of end-to-end solutions and application portability across multiple client and server platforms.