With the emergence of mobile computing devices such as Personal Digital Assistants (PDAs), a new challenge to design methods of interacting with them for people with disabilities has been created. In this paper, we propose GrooveWrite as a novel text entry system for handheld devices equipped with touch screen and stylus, targeted at people with situational and motor impairments. Based on traditional seven-segment layout, GrooveWrite interface is designed and implemented. The characters are entered by moving the stylus inside physical side-grooves, which are used as a stabilizer for stylus motion, and crossing the subset of segments that forms intended character. Character recognition neither considers the path of movement, nor recognition pattern, but only the subset of seven segments that is crossed. We examine our system theoretically using CLC model. This study shows that GrooveWrite text entry speed will be 24.78 words per minute.