Although text messaging services are becoming increasingly popular in today's global wireless market, fundamental design issues still linger with respect to text entry methods on mobile communication devices. Current methods may often be plagued with problems such as poor typing efficiency, stringent physical size limitations, and an unwarranted cognitive processing burden on mobile users. The proposed text entry method for mobile communication devices, called SIMKEYS, balances input efficiency, ergonomics, usability, and cost via a compact 12-button keypad. Pursuing a deterministic and linguistically optimized approach to character disambiguation, SIMKEYS achieves significant improvement in typing performance over existing methods, verified by extensive simulation results. It also consumes negligible amounts of system resources and incurs minimal development costs. Because of its simplicity and efficiency, SIMKEYS opens the door to exciting opportunities in the next stage of development of the wireless Internet.