Patent ID: 8250493

Claim:
A user interface method, comprising: measuring acceleration of an input device while a gesture writing is performed, using the input device to generate acceleration signals, wherein the gesture writing is performed while a button of the input device is activated; determining whether the input device is operated relative to a predetermined gesture range based on a time period when the gesture writing is made and/or based on the acceleration signals; generating a first warning or a second warning indicating that the input device has deviated from the predetermined gesture range when the input device deviates from the predetermined gesture range and outputting a first or second warning message corresponding to the first or second warning to a user; and generating a third warning indicating that the button has been temporarily released from activation, when the button is deactivated and re-activated within a predetermined time during the gesture writing and outputting a third warning message corresponding to the third warning to the user, wherein the first warning, second warning, and third warning are at least one of a verbal warning message, a displayed message on a display, and a form of vibration, and wherein the button is separate from the display.