Design user interfaces for viewing and interacting with data and operations on the mobile device.
Consider what data and how much to present on the device (within memory limitations and other device constraints), and how to create data subsets for limited resources on the device. Remember that each device platform has different controls and physical forms that determine presentation and how the user interacts with the data.
Use storyboards to plan the screen flow and decision points. Create "mockup" screen designs that specify placement of controls, logic, and validation logic. Determine what changes may be needed to adapt the design for specific device types. Identify any customization that may be needed. You can use the Device Application Designer to design and create prototype BlackBerry and Windows Mobile device applications.
See Sybase Unwired WorkSpace – Device Application Development for information about tools for prototyping the user interface.