The Object API application model enables developers to write custom code — C#, Java, or Objective-C, depending on the target device platform — to create device applications. 
Development of Object API applications provides the most flexibility in terms of leveraging platform specific services, but each application must be provisioned individually after being compiled, even for minor changes or updates. 
Development involves both server-side and client-side components.
                    SAP Mobile Server brokers data synchronization and transaction
                processing between the server and the client components.
- Server-side components address the interaction between the
                        enterprise information system (EIS) data source and the data cache. EIS data
                        subsets and business logic are encapsulated in artifacts, called mobile
                        business object packages, that are deployed to the
                        SAP Mobile Server.
- Client-side components are built into the mobile application
                        and address the interaction between the data cache and the mobile device
                        data store. This can include synchronizing data with the server, offline
                        data access capabilities, and data change notification. 
These applications:
- Allow users to connect to data from a variety of EIS systems, including SAP® systems.
- Build in more complex data handling and logic.
- Leverage data synchronization to optimize and balance device response time and need for real-time data.
- Ensure secure and reliable transport of data.