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Guidelines for Mobile Interface Design
The interface design is a critical factor for the success of any application. The now proposed guidelines seek to improve the user experience and apply to the majority of the applications for mobile devices.
Enable shortcuts for frequently used functions
Time is a critical factor for the users that generally need “Just in time” information in the mobile context. That is why, reducing the amount of steps required for the user to perform frequent operations facilitates his adaptation to the application device.
Maintain the used informed of its actions
Always maintain the user informed about what is happening in the application.. It can be done using sounds, dialogs, messages, etc.
Follow the device’s interface patternUsing the system’s native interface components reduces the learning curve of the user regarding the application once the interface will be similar to others that he is already used to.
It's a subset of the last section. It is important to pay attention to the menu positioning on the screen. For example, in the Nokia devices in general have the application trigger located on the left side of the screen while on the right is located the trigger used to cancel an action. The same positioning is used for YES/NO actions.
 - G ONG , J., AND TARASEWICH , P. 2004. Guidelines for handheld device interface design. In Proceedings of DSI 2004.